Abstract
This study aimed to investigate the mediating role of self-esteem in the relationship between spiritual intelligence and marital adjustment. The research employed a descriptive correlational design. The statistical population consisted of married individuals attending psychology counseling centers located in Districts 1, 9, 10, 11, 14, and 17 of Mashhad during September and October 2024. The estimated number of individuals in the statistical population was 300. Initially, 300 married individuals were selected through proportional stratified random sampling. Based on the Krejcie and Morgan table (1970), the sample size was determined to be 169 participants, including 100 women and 69 men. After screening the questionnaires and excluding incomplete and invalid responses, the final sample consisted of 169 participants, including 100 women and 69 men. Proportional stratified sampling was used, and after determining the proportion of each stratum, eligible individuals were randomly selected. The questionnaires were provided to the selected individuals online through a web-based platform, and after reviewing the responses, incomplete and invalid questionnaires were excluded. Data were collected using the Spanier Dyadic Adjustment Scale (1976), the King Spiritual Intelligence Self-Report Inventory (SISRI-24; 2008), and the Coopersmith Self-Esteem Inventory (1965). Data were analyzed using SPSS and SmartPLS software. The findings indicated that spiritual intelligence had both a direct (β = 0.42, p < 0.01) and an indirect positive and significant effect on marital adjustment through self-esteem (β = 0.35, p < 0.01). In addition, significant positive relationships were found between spiritual intelligence and self-esteem, as well as between self-esteem and marital adjustment. Structural equation modeling further demonstrated that self-esteem significantly mediated the relationship between spiritual intelligence and marital adjustment. These findings suggest that spiritual intelligence enhances marital adjustment by increasing self-esteem and emphasize the importance of considering psychological and spiritual variables in marital counseling and couple therapy interventions.