Investigating the mediating role of moral identity on the relationship between spiritual intelligence and Muslims’ self-esteem

their value as members of the organisation (Lowe & Harris 2019). Self-esteem has attracted the attention of many psychologists and educational researchers. Self-esteem means a person’s judgment of their worth; this judgment is made by comparing their own performance against the standards of others and coping with the result. Self-esteem is how you feel about yourself (Orth & Robins 2013). One of the critical crises observed in human society, especially in the so-called advanced and industrial societies, is the spiritual crisis. Spirituality in various types of cultural and religious concepts is considered a spiritual path one in which can achieve something like a high level of consciousness, wisdom or union with God. In addition, self-esteem is a sense of worth. This feeling comes from the sum of our thoughts, feelings, emotions and experiences throughout life. Dignity also means honour and pride, which has been mentioned many times in the Qur’an. In contrast to dignity, there is humiliation, which means lack of dignity in which one simply accepts defeat. Religious teachings, especially Islamic teachings, do not summarise dignity as wealth, luxury and the enjoyment of material possibilities, but interprets dignity as spirituality, and liberation from the shackles of worldliness, which give Muslims a moral identity. The main purpose of this study is to investigate the mediating role of moral identity between spiritual intelligence and self-esteem of Muslims. The statistical population includes 834 Muslim employees working in 20 branches of one Iranian university. Necessary data were collected by standard questionnaires. Pearson’s correlation coefficient and regression analysis in SPSS software (Statistical Package for the Social Sciences) were used to analyse the data. According to the results of the analysis, there is a positive relationship between spiritual intelligence and self-esteem of Muslims. There is also a positive relationship between moral identity and self-esteem. Furthermore, moral identity plays a mediating role in the relationship between spiritual intelligence and self-esteem, and it strengthens this relationship. Contribution: The present study proves the mediating role of ethical identity on the relationship between spiritual intelligence and self-esteem in an Islamic society.


Introduction
Self-esteem is one of the most important issues in mental health, which is one of the most important and basic characteristics of each person's personality and affects other personal aspects of human beings. The lack of self-esteem will cause other aspects of personality to grow or become out of balance and may be the cause of shyness, aggression, fear and various mental illnesses such as depression (Fatima, Niazi & Ghayas 2017). Self-esteem means a person's confidence in their own worth or abilities. Maintaining and promoting the self-esteem of employees is one of the most important ways to increase motivation. The way employees perceive themselves in the workplace influences their attitudes, motivations and work behaviours. Employees have judgements about themselves which are important for their organisation.
Self-esteem is an overall assessment of each person's worth. Self-esteem shows a person's level of self-awareness to perform specific tasks. Self-esteem is the perception that people have of their value as members of the organisation (Lowe & Harris 2019). Self-esteem has attracted the attention of many psychologists and educational researchers. Self-esteem means a person's judgment of their worth; this judgment is made by comparing their own performance against the standards of others and coping with the result. Self-esteem is how you feel about yourself (Orth & Robins http://www.hts.org.za Open Access Self-esteem includes the structures that provide a person with peace of mind. Self-esteem plays a protective role in dealing with stress that safeguards a person from the stressful events of life. A person of high value easily confronts external threats without experiencing the disintegration of the organisation. Low self-esteem has been observed as a risk factor for aggression, delinquency, substance abuse, depression, poor academic performance, spouse abuse, child abuse and the like (Potter et al. 2014). Self-esteem is one of the most fundamental aspects of our personality and determines our behavioural characteristics (Holas et al. 2021). Identity is a broad concept that includes individual, religious, moral, collective, group, national, ethnic and transnational identities. Moral identity is one of the types of identity, a dynamic system within the individual that influences the behaviour of the person (Aquino & Reed 2002). In other words, in the definition, qualities such as justice, compassion, generosity, humility and selflessness play an important role, as a sense of adherence to these attributes in practice and in dealing with others (Matsuba, Theresa & Hart 2011). The individual's sense of self-satisfaction is also associated with the emergence of these traits (Hart & Atkins 1999).
Moral identity is a mechanism that stimulates moral action. Furthermore, our mental constructs, including mental schemas of moral action and moral personhood, along with the evolution of our moral perception, can be linked to our sense of identity and lead to what we call moral identity. But it is beyond the scope of this research to determine whether morality is rooted in a kind of identity connection with the moral person, which means that there is a certain importance and commitment to morality, or that we act morally merely because a moral judgment has led us to do so. Therefore, the main aim of this study is to investigate the mediating role of moral identity on the relationship between spiritual intelligence and Muslims' self-esteem amongst the Muslim employees of 20 branches of one Iranian university in 2021.

Theoretical background
Self-esteem manifests itself in different ways, but in general it can be seen in the face, behaviour, speech and movement of people. An example of self-esteem is dealing openly with criticism, and accepting mistakes in an easy manner. In other words, the manner of speech and actions of people with selfesteem have a comfortable quality. Their movements show that they are not at war with themselves and not at war with others (Leary & MacDonald 2003); and their feelings in this world depend on what they want to be or do.
There are several references to self-esteem in the Holy Qur'an, which shows the high importance of this concept. For example, the Qur'an states: 'This is a book revealed by God almighty and wise which shows the glory of God and also the Holy Qur'an' (Surah Az-Zumar, Ayat 1). In the present age, when organisations need to respond quickly, it seems that newer and deeper intelligence is needed to help employees in this critical matter (especially in an Islamic environment).
Today, it is argued that organisations have felt the need to understand the concept of spirituality; therefore, researchers have tried to explore these concepts to clarify the issue. It is worth noting that for a long period, the topics of religion and spirituality have not received much attention in various studies. Pargament and Saunders (2007) argue that firstly, some psychologists believe that psychology is a science that uses rigorous scientific methods, whereas the religious sciences are more philosophical. Secondly, religious issues are sometimes associated with spirituality. Finally, in the 20th century, psychoanalysis and behaviourism were the two dominant approaches in psychology. Because these two perspectives ignore religious experiences, the study of religion and spirituality has received less attention in psychology.
But in the last two decades, the study of spiritual subjects has received increasing attention, and a new concept has entered the field of psychology and management, which is spiritual intelligence. After extending the concept of intelligence to other realms, human capacities and abilities, and especially the introduction of emotional intelligence in psychology, Emmons in 1999 introduced a new concept called spiritual intelligence. He stated that spiritual intelligence is a set of abilities to use religious and spiritual resources. Spiritual intelligence combines the structures of intelligence and spirituality in one structure. Spirituality is the search for sacred elements, meaning-seeking, high awareness and transcendence; while spiritual intelligence includes the ability to use such subjects to predict a person's ability to function and adapt, leading to valuable results. Emmons (1999Emmons ( , 2000aEmmons ( , 2000b offers various definitions of intelligence, but the core of all these definitions is the focus on problem-solving to adapt and to achieve goals. For example, Emmons (2000aEmmons ( , 2000b defines intelligence as the ability to achieve goals in the face of obstacles based on decisions that are based on rational principles. He goes on to say that intelligence is a set of abilities that allow a person to solve problems based on a particular cultural environment. If we consider the ability to benefit from spiritual resources as an intelligence, then this ability should help solve people's problems and achieve goals, leading to their better adaptation. Research shows that there is a positive relationship between spirituality and life satisfaction, health and well-being (Cole 2005;George et al. 2000;Pargament & Saunders 2007;Shafranske 2001;West 2000). Therefore, spiritual abilities can bring positive effects and beneficial results to an individual, especially when these results are evaluated based on the social and cultural environment of individuals. In addition, Gardner (1993) proposed his theory of multiple intelligences, stating that if we want to consider a set of capacities or abilities as intelligence, we must consider eight criteria: (1) it should include a set of specific activities, (2) it should have an evolutionary history and seem rationally evolutionary, (3) it should have a specific pattern of growth, (4) it should be identifiable through brain damage, (5) it should be classifiable in the extent of that ability or lack thereof, (6) it should have the ability to encode with a symbolic system, (7) it should be supported by experimental psychological studies and (8) it should be supported by psychometric findings. It is worth noting that Emmons (2000a) believes that spiritual intelligence has these eight criteria.
In addition, spirituality as one of the dimensions of humanity includes awareness and self-knowledge. Spirituality is the need to transcend oneself in the life of the soul and to be integrated with someone other than ourselves. This awareness may lead to an experience that is beyond ourselves (Koenig 2011). Spirituality is a universal quality, and like excitement, it has different degrees and effects. It may be conscious or unconscious, developed or immature, healthy or pathological, simple or complex, useful or dangerous (Yang & Mao 2007 . When people deeply understand their inner mistakes, they will not repeat them, therefore, they will be freed from the fear and confusion of making mistakes. They will be freed from fear and turmoil in the face of change, which is the deepest level of spiritual intelligence. Machovec (2002) and Emmons (2000a) stated that spiritual intelligence can be used to solve daily problems; meanwhile Wolman (2001) considered spiritual intelligence to be the basis for solving existential and moral problems. They also distinguish between using spiritual intelligence to solve problems and using them to solve nonspiritual problems.
A person who is nearing the end of his or her life may experience spiritual values and existential beliefs to illuminate a sense of meaning at this stage of life. An example of this process can be a manifestation of spiritual intelligence, but the important point that this view overlooks is that in a spiritual person, all aspects of their life will be spiritual. The idea of separating spiritual issues and problems from nonspiritual ones is challenging to apply different problemsolving strategies. The search for meaning and seeing a larger concept of life can encompass almost every event and experience in life. Similarly, some abilities and attributes of spiritual intelligence, such as wisdom, self-awareness, creative reasoning, perfection, compassion and asking 'why' questions, may be related to higher issues and problems, apart from spiritual or existential issues (Steger et al. 2006).
Moral beliefs of every human being, especially in adolescence and beyond, are often fundamental parts of identity. Adolescents perceive themselves mainly in the context of interpersonal relationships and belief systems. Both of these attributes are closely related to moral values and beliefs. A teenager who considers themselves a generous, fair, altruistic and truthful person has identified themselves with the criterion of moral values (Salmabadi et al. 2016). Moral identity can be considered in the form of a commitment to individual feeling for a set of actions and behaviours that promote the well-being and happiness of others, and it is a reflection of the importance of a set of moral characteristics for the individual. Moral identity is actually a mechanism that stimulates moral action (Aquino & Reed 2002). Each person has the capacity to gain an identity in relation to others in a variety of variables, including habits, family contacts and personal interests.
This identity can also be related to higher level social identities such as political or religious identity. Most of the social identities with which people define themselves are recognised as structural and unique knowledge in an individual's memory. Therefore, it seems wise that personal perceptions can be considered as organisers of a person's moral personality, and moral identity is part of a person's social profile. Moral identity is defined as a person's personal perception of themselves about a set of characteristics. The definition of moral identity is influenced by transformationalcognitive theories. Therefore, although some definitions of moral qualities are mentioned in these definitions, in fact, attention is paid to how a moral person thinks. In fact, although the root of moral identity is in the concepts of personal traits and characteristics, it is assumed that the moral identity of a society also has its roots in membership in real groups (Shao, Aquino & Freeman 2008).

Methodology
The present study is considered as an applied research in terms of purpose. In terms of methodology, it is a descriptivecorrelational research. In this type of research, the researcher, without intervening in the situation, simply collects data and describes and estimates the correlation between variables. The statistical population of the study includes 834 Muslim employees working in 20 branches of one of the Iranian universities in various cities in 2021. Standard questionnaires were used to collect data by simple random sampling method amongst the statistical population.
The Aquino and Reed (2002) questionnaire was used to assess the moral identity of Muslims. This questionnaire consists of 10 questions and two indicators of internalisation and externalisation.
In addition, the King (2008) questionnaire with 24 questions was used to assess spiritual intelligence. This questionnaire examines indicators such as critical existential thinking, production of personal meaning, development of state of consciousness and transcendent consciousness in Muslims.
Finally, the Rosenberg (1965) questionnaire was used to measure the self-esteem of Muslims. This questionnaire includes 10 self-report questions that express one's overall sense of worth or acceptance in a positive way. After distributing the questionnaires, the researchers collected 813 questionnaires and began the analysis process. Amongst the participants, 657 were men and 156 were women. Seven hundred eighty-one of these participants were married and 32 were single. Twelve per cent were under 30 years old, 67% were between 30 and 45 years old and 21% were over 45 years old. Cronbach's alpha in SPSS software was used to assess the validity of the questionnaires (Table 1). Table 1 shows the descriptive findings including mean, standard deviation and Cronbach's alpha of the variables of spiritual intelligence, moral identity and self-esteem.

Research findings
In addition, Table 2 shows the correlations between the research variables. This correlation was calculated by Pearson's test in SPSS software. Positive figures indicate a positive correlation between research variables.
In order to investigate how the two variables affect each other, the method of multiple regression analysis was used simultaneously. In addition, in order to investigate the mediating role of moral identity between spiritual intelligence and self-esteem, the proposed steps of Baron and Kenny (1986) were used. As a result, in the first stage, regression of spiritual intelligence on self-esteem was performed (Table 3); in the second stage, regression of spiritual intelligence on moral identity was performed (Table 4), and in the third stage, regression of spiritual intelligence and moral identity on self-esteem (Table 5) was performed. The result of each step was entered in the form of tables.
In Table 3, the multiple correlation coefficient was 0.301 and the R-square coefficient was 0.091. A coefficient of R-square indicates that 9% of the variance in self-esteem can be justified through spiritual intelligence. Comparison of β factor also showed that spiritual intelligence of 0.535 predicts self-esteem.
In Table 4, the multiple correlation coefficient was 0.410 and the R-square coefficient was 0.168. The coefficient of determination shows that 16% of the variance of moral identity can be justified through spiritual intelligence. Comparison of β coefficient also showed that spiritual intelligence of 0.391 predicts moral identity.
In Table 5, the multiple correlation coefficient was 0.360 and the R-square coefficient was 0.130. The coefficient of determination shows that 13% of the variance of self-esteem can be justified through spiritual intelligence and moral identity. Comparison of β factor also showed that spiritual intelligence and moral identity indirectly predict moral identity by 0.377 and 0.404, respectively. The results showed that spiritual intelligence predicts self-esteem in Muslims, both directly and indirectly, by influencing moral identity. Table 6 shows the direct and indirect effects of independent and mediating variables on the dependent variable. The study of the overall effects indicates that the variable of spiritual intelligence has the greatest impact on changes in self-esteem; the variable of moral identity is in the next category of influence.

Discussion and conclusion
These days, we are witnessing intermittent technological advances and an unprecedented increase in welfare facilities around the world. Unfortunately, the result of these developments is a decline in values in people's lives, which can be a brief explanation of why so many people in our society are depressed and distressed. Recently, the idea of spirituality has been on the rise in various publications. Given the fact that individuals are inherently endowed with spiritual capacity and intelligence, it seems that individuals who integrate spirituality with their lives and careers will gain a positive perspective. According to Wolman (2001), people who work in a positive spiritual environment and also have higher spiritual intelligence show higher performance. Spiritual intelligence is the basis of each person's beliefs, which increases the flexibility of individuals in the face of difficulties and problems. The existence of spiritual intelligence in life promotes human flourishing. As a result, people have high spiritual intelligence, a high capacity for excellence and a desire for awareness. These people have the ability to easily transform their potential into actual capacity. These people dedicate a part of their daily activities to spiritual works and show virtues such as forgiveness, gratitude, humility, compassion and wisdom.      Therefore, it seems that people who have a higher capacity of spiritual intelligence will show positive behavioural and personality traits and will have favourable conditions in terms of mental health and, of course, physiological health.
In the modern age, societies face many social, cultural and economic problems. Most experts believe that solving many of the existing problems requires citizens who not only have wisdom, but also equally remarkable social skills. Intelligence is one of the most influential concepts of psychological processes, the effects of which are observed in different organisms to different extents. The more evolved creatures become, the more advanced and complex they are in terms of intelligence. Also, the field of spirituality is developing today in various fields such as medicine, psychology, anthropology, cognitive sciences and theology. Today, attention to the concept of intelligence and spiritual abilities in humans has formed a new internal structure called spiritual intelligence. The concept of spiritual intelligence is a multidimensional structure and includes the interaction between intelligence and spirituality that leads to adaptive human behaviours. These adaptive behaviours in humans, in turn, lead to good physical and mental health.
In the original culture of Islam, implicitly, spiritual intelligence has received much attention. Spiritual intelligence in human beings is a divine gift that is considered the inner prophet of human beings, and according to its nature, it desires goodness and perfection and demands justice. This intelligence is the criteria for discerning right from wrong, good from evil; with this intelligence, ugliness is distinguished from beauty, and perfection from vileness. Factors affecting spiritual intelligence in Islamic texts are belief in God, piety and daily exercises such as contemplation of creation, contemplation of the horizons, fasting, worship, reading the Qur'an and sincere contemplation of its verses.
Some abilities and characteristics such as wisdom, creativity and compassion that grow with spiritual awareness come from religion. We can cultivate ourselves as religious people by developing spiritual intelligence. Spiritual intelligence teaches people compassion, kindness, unity in differences and meaningful reliance, and strengthens self-esteem in people, which has been addressed in the present study. Psychological studies suggest that if the need for self-esteem is not met, especially in young people, broader needs such as the desire for creativity, initiative, progress and understanding of potential talents are limited.
Dignity also means having honour, feeling pride and being cherished. The word honour means a state that does not allow humans to fail and be defeated. In contrast to dignity, there is humiliation, which means a lack of honour and greatness in humans, in such a way that a person simply accepts defeat. In religious teachings, dignity is not summed up in wealth, luxury and the enjoyment of material possibilities, but dignity is interpreted in slavery, spirituality, liberation from bondage, lust and worldliness. Self-esteem is one of the basic foundations of human personality and causes human beings to achieve honour and pride. Self-esteem is the source of freedom and excellence. Honourable persons never submit to humiliation and servitude of others and do not trade their capital of honour and freedom at any price. This precious gem can be enhanced by spirituality and spiritual intelligence, as the results of the present study have shown. Religious beliefs and practices within an individual enable the individual to physiologically, cognitively and emotionally control their anger and help them take responsibility for their actions in conflicts. Interpersonally, religious practices create the conditions for the individual to pay attention to God when angry. Spirituality is an organised system of beliefs that includes moral values, customs and participation in a religious community for a stronger belief in God or a higher power. Religious beliefs are an effective way to deal with suffering and painful experiences. They also affect how human relationships work in times of trouble and distress. The believer, who has spiritual connections and beliefs, feels less abandoned, empty and lonely, achieves a moral identity in life that has been emphasised in this study.
Spiritual intelligence provides humans access to meaning and value as well as its use in thinking and making decisions; therefore, it seems that people with high spiritual intelligence are less likely to have mental problems. Spiritual intelligence includes a type of adaptation and problem-solving behaviour that includes the highest levels of development in various cognitive, moral and emotional areas, and it helps an individual to adapt to the circumstances around them and achieve internal and external integration and mental health. Spiritual intelligence gives a person an overview of life and the work environment, leading them to inner and outer peace, which plays a very important role in people's mental health. According to the results of this study, there is a direct and significant relationship between spiritual intelligence and self-esteem. On the other hand, the research results indicate that there is a direct and significant relationship between moral identity and self-esteem. This means that as moral identity rises, so does self-esteem. Moral identity also mediates the relationship between spiritual intelligence and self-esteem. According to the results of this research, it is worthwhile for managers of organisations and rulers of Islamic society to pay special attention to the components of spirituality, moral identity and self-esteem in order to benefit from their advantages.