Spiritual Maturity Index

Abstract

The Spiritual Maturity Index (SMI) is an operationalized psychometric instrument developed by Craig W. Ellison in 1984, designed to measure religious and spiritual maturity as an ongoing, continuous developmental process. Grounded in both developmental psychological theory and evangelical Christian theology, the SMI operationalizes spiritual maturity not merely as subjective affective well-being or denominational affiliation, but as an integrated constellation of cognitive autonomy, behavioral discipline, sacrificial love, theological openness, and personal identity anchored in communion with the transcendent. The instrument comprises 30 self-report items evaluated on a 6-point Likert-style response continuum ranging from “Strongly Disagree” to “Strongly Agree,” featuring 18 positively keyed items and 12 reverse-scored items. Across empirical investigations, the SMI demonstrates high internal consistency, with reported Cronbach’s alpha coefficients ranging between .87 and .92. Exploratory and confirmatory factor analyses consistently point to a strong, dominant general factor of internalized faith commitment and spiritual praxis, aligning with classical psychometric models of religiosity. Construct validity is supported by moderate to strong correlations with Ellison’s Spiritual Well-Being Scale (SWBS; r = .57 to .62) and meaningful differentiation in known-groups paradigms. This article provides an exhaustive psychometric exposition of the SMI, examining its theoretical architecture, measurement model, standardization history, empirical validity, reliability metrics, and practical administrative parameters for clinical, pastoral, and empirical research contexts.

Keywords

Spiritual Maturity Index, SMI, Craig W. Ellison, spiritual maturity, psychology of religion, psychometrics, Spiritual Well-Being Scale, Christian developmental psychology, religious commitment, internal consistency

Authors

The Spiritual Maturity Index was developed by Craig W. Ellison, Ph.D., who served as Professor of Urban Studies and Counseling at Alliance Theological Seminary (Nyack, New York). Dr. Ellison is widely recognized in the psychology of religion for his pioneering conceptualization and measurement of spiritual health, most notably as the co-developer (with Raymond F. Paloutzian) of the widely utilized Spiritual Well-Being Scale (SWBS). His scholarly agenda focused on the intersection of developmental psychology, mental health, urban ministry, and Christian theology.

Purpose

The primary purpose of the Spiritual Maturity Index is to provide an empirically tractable, continuous metric of spiritual growth and functioning within an Judeo-Christian theological paradigm. Historically, empirical research in the psychology of religion struggled with instruments that conflated religious maturity with mere institutional adherence, doctrinal orthodoxy, or affective comfort. Ellison sought to delineate a quantitative assessment tool that evaluates the extent to which an individual exhibits substantive spiritual integration, characterized by behavioral, attitudinal, and identity markers analogous to psychological maturity.

In empirical and developmental research, the SMI serves to illuminate the longitudinal trajectories of faith development. Rather than categorizing individuals into rigid, discontinuous stages, the scale treats spiritual maturation as a fluid continuum ranging from externalized, derivative faith to internalized, autonomous, and self-sacrificial spiritual living. It enables researchers to investigate how spiritual growth interacts with personality dimensions, cognitive complexity, moral reasoning, coping mechanisms, and marital or interpersonal dynamics.

In clinical, pastoral, and educational contexts, the SMI offers diagnostic utility. In seminary training and ministerial candidacy assessments, the instrument assists faculty and spiritual directors in identifying areas where a student may rely excessively on institutional consensus rather than deep-seated personal convictions, or where a student struggles to integrate faith into daily relational and vocational demands. In Christian counseling and clinical psychology, the SMI can assist clinicians in differentiating between mature religious coping—which facilitates resilience, meaning-making, and constructive endurance through suffering—and defensive or immature spiritual bypass mechanisms characterized by rigidity, guilt, or extrinsic religious dependence.

Psychological Construct

The construct assessed by the SMI is Spiritual Maturity, operationalized as an individual’s progressive internalization and practical enactment of classic Christian virtues, spiritual disciplines, and existential integration. Ellison conceived spiritual maturity as bearing structural parallels to psychological maturity, drawing from principles of ego development, autonomy, and relational maturity.

The construct encompasses several interrelated behavioral, cognitive, and affective facets:

• Autonomous Faith Commitment vs. Institutional Dependence: Mature spirituality involves cultivating a vibrant, resilient faith that does not rely exclusively on the institutional church, peer validation, or external social scaffolding. While valuing communal fellowship, the spiritually mature individual maintains deep-seated convictions even in the face of cultural opposition or social disapproval.
• Pervasiveness and Daily Integration: In contrast to compartmentalized religion, maturity denotes the permeation of spiritual awareness throughout daily routine. Daily decisions, thought patterns, vocational activities, and relationships are actively influenced by an ongoing sense of communion with God.
• Cognitive Openness and Epistemic Humility: Ellison posited that spiritual maturity demands a keen perception of reality and openness to new insights, balanced with theological grounding. A mature faith rejects dogmatic defensiveness, judgmentalism, and the tendency to label ideological dissenters as “hard-hearted.”
• Identity Anchored in the Transcendent: The individual’s core sense of self-worth and identity is derived from an intimate relationship with God, superseding social status, professional achievements, or circumstantial fluctuations.
• Altruism, Sacrificial Love, and Spiritual Gifts: A hallmark of maturity is the deliberate pursuit of Christ-like altruism, characterized by a willingness to prioritize the welfare of others, steward personal spiritual gifts, and embrace self-sacrifice without descending into co-dependence or self-effacing pathology.
• Transformative Coping with Adversity: Spiritually mature individuals reframe existential crises, personal pain, and profound suffering as developmental catalysts that foster greater intimacy with God, rather than viewing hardship as divine betrayal or cause for spiritual despair.
• Spiritual Disciplines and Developmental Intimacy: Conscientious engagement in personal prayer, meditative scripture study, and contemplation serves as the engine of spiritual vitality, fueling moral transformation and victory over internal impulses.

Theoretical Framework

The theoretical architecture of the Spiritual Maturity Index synthesizes developmental psychology, existential personality theory, and evangelical Christian theology. Ellison drew significantly from Gordon Allport’s foundational taxonomy of intrinsic versus extrinsic religious orientations. Allport posited that while extrinsically religious individuals utilize religion as an instrumental means toward utilitarian ends (such as social status or emotional comfort), intrinsically motivated individuals live their religion, integrating faith as an overarching, master-motive that organizes their entire personality. The SMI operationalizes this intrinsic orientation while enriching it with specific theological markers of Christian character.

Furthermore, the SMI intersects with Erik Erikson’s psychosocial stages of development, particularly the cultivation of ego identity versus role confusion and generativity versus stagnation. Spiritual maturity reflects an integrated ego identity capable of genuine psychosocial intimacy and self-transcendent generativity, manifesting in the willingness to pour resources into the development of others and future generations.

Ellison also integrated concepts from James W. Fowler’s stages of faith development, particularly the transition from Synthetic-Conventional Faith (where identity is tied to group consensus and external authority) to Individuative-Reflective Faith and Conjunctive Faith. In Fowler’s paradigm, mature faith demands critical self-reflection, the dismantling of unexamined cultural assumptions, and the capacity to tolerate paradox and mystery. The SMI operationalizes this developmental shift through items that contrast blind reliance on external Christian support with internal personal resolve and openness to ongoing theological revelation.

Theologically, the scale is anchored in the Pauline and Johannine motifs of spiritual transformation (e.g., Romans 12:1-2; Galatians 5:22-23; Ephesians 4:11-16). Spiritual growth is conceived not as static sinlessness, but as an ongoing teleological process toward Christ-likeness, sustained by internal divine grace and manifested in tangible ethical fruits, sacrificial service, and devotional intimacy.

Validity

Empirical evaluations of the Spiritual Maturity Index provide critical insight into its psychometric profile, revealing robust convergent relationships alongside continuous debate regarding its discriminant uniqueness from generalized religiosity.

Convergent and Concurrent Validity

Ellison’s (1984) initial validation work established a significant positive correlation between the SMI and the Spiritual Well-Being Scale (r = .57, p < .001). This convergence was replicated by Bufford (1984), who observed a correlation of r = .62 across adult Christian samples. Subsequent investigations (e.g., Boliou et al., 1987; Cooper, 1987; Davis et al., 1987; Mack et al., 1987) confirmed strong convergent associations between the SMI and various indices of personal prayer frequency, scriptural study, and Christian commitment. McPherson (1990) demonstrated that higher SMI scores correlated positively with optimal religious functioning and adaptive personality profiles, including emotional stability and conscientiousness.

Discriminant and Construct Validity Critiques

Despite its theoretical distinction from spiritual well-being (where well-being represents affective health and maturity represents behavioral/attitudinal virtue), empirical studies have questioned the instrument’s discriminant validity. In an extensive comparative analysis of Christian maturity scales, Bassett et al. (1991) factor-analyzed the SMI alongside several competing religiosity instruments. Their findings revealed that items from the SMI collapsed heavily onto a singular, pervasive factor capturing generalized personal religious commitment, echoing Richard L. Gorsuch’s (1984) psychometric critique that multidimensional religiosity instruments frequently tap into a single, dominant “general religious commitment” factor. Thus, while the SMI displays high face and content validity among Christian populations, its empirical construct separation from intrinsic religiosity remains modest.

Known-Groups Validity

Buhrow et al. (1987) assessed known-groups validity within religious cohorts. The SMI effectively discriminated between participants who self-identified as “professing Christ as personal Savior” versus individuals who characterized themselves merely as “followers of Christ’s moral teachings,” with the former group obtaining significantly elevated maturity scores. Gender differences across multiple validation cohorts have consistently been non-significant, suggesting measurement invariance across male and female respondents.

Reliability

The Spiritual Maturity Index exhibits high internal consistency across a diverse array of theological and educational samples:

• Internal Consistency: In an initial psychometric appraisal among 117 seminary students across three institutions, Buhrow et al. (1987) obtained a Cronbach’s alpha of .87. In a later multi-institutional comparison involving university undergraduates, Bassett et al. (1991) documented an alpha coefficient of .92 across Protestant and Catholic cohorts, demonstrating exceptional item interrelatedness and measurement precision.
• Test-Retest Stability: Although Buhrow et al. (1987) administered a six-month retest battery to a subsample of theological students, formal longitudinal stability coefficients were unfortunately omitted from the published records. Theoretical considerations suggest that because spiritual maturity reflects a slowly evolving developmental trait rather than a fluctuating emotional state, test-retest coefficients over short intervals (e.g., 2 to 4 weeks) would be expected to exceed .80, though formal empirical confirmation across diverse cohorts is needed.
• Standard Error of Measurement: Given observed standard deviations averaging approximately 17.0 points across adult cohorts and alpha levels near .90, the estimated Standard Error of Measurement (SEM) approximates 5.37 points, providing a dependable confidence band for individual score interpretation in pastoral and research applications.

Factor Analysis

Multiple factor analytic investigations have explored the internal structure of the 30-item SMI to determine whether it functions as a multidimensional battery or a unidimensional index.

Exploratory Factor Analyses (EFA)

Early factor analyses conducted on Christian adult and student populations (e.g., Barker et al., 1987; Cooper, 1987; Davis et al., 1987) consistently revealed a dominant primary factor accounting for a substantial portion of the total item variance (typically between 30% and 42%). While secondary and tertiary factors frequently emerged in unconstrained orthogonal or oblique extractions—tentatively corresponding to “Devotional Disciplines,” “Autonomous Conviction,” and “Altruistic Fruitfulness”—the substantial item cross-loadings and the sheer magnitude of the first unrotated eigenvalue supported the calculation of a single composite score.

Structural Integration Studies

In the seminal structural investigation by Bassett et al. (1991), exploratory and joint factor analytic procedures were executed combining items from the SMI, the Spiritual Well-Being Scale, and several established Christian maturity measures. The analysis revealed a dominant global factor that the authors described as capturing “the extent to which personal commitment was manifested in belief and practice” (p. 90). The 12 reverse-scored items consistently aligned inversely with this central axis. Consequently, psychometric consensus views the SMI as an essentially unidimensional measure of personal Christian commitment and maturity, wherein subscale extraction lacks robust structural support.

Instrument / Measurement Tool

The physical instrument and scoring structure of the SMI are organized as follows:

• Test Type: Self-report psychological/spiritual rating scale.
• Administration Format: Paper-and-pencil or computer-assisted self-administered questionnaire.
• Completion Time: Approximately 8 to 10 minutes.
• Total Number of Items: 30 items.
• Response Continuum: 6-point forced-choice Likert-style format without a neutral midpoint:
• SA = Strongly Agree (scored 6 for positive items, 1 for reverse items)
• MA = Moderately Agree (scored 5 for positive items, 2 for reverse items)
• A = Agree (scored 4 for positive items, 3 for reverse items)
• D = Disagree (scored 3 for positive items, 4 for reverse items)
• MD = Moderately Disagree (scored 2 for positive items, 5 for reverse items)
• SD = Strongly Disagree (scored 1 for positive items, 6 for reverse items)
• Positively Scored Items (18 items): 1, 2, 4, 6, 7, 11, 13, 16, 17, 19, 20, 22, 23, 25, 26, 27, 28, 30. Scored: SA=6, MA=5, A=4, D=3, MD=2, SD=1.
• Reverse-Scored Items (12 items): 3, 5, 8, 9, 10, 12, 14, 15, 18, 21, 24, 29. Scored: SA=1, MA=2, A=3, D=4, MD=5, SD=6.
• Scoring Summation: Total raw scores range from 30 to 180 points. Higher composite scores represent higher levels of spiritual maturity.
• Normative Reference Values:
• Adult Protestant Sunday School Attendees: Mean = 138.10, SD = 16.80 (Mack et al., 1987).
• Seminary Graduate Students: Mean = 140.73, SD = 17.78 (Buhrow et al., 1987).
• Protestant Undergraduate Students: Mean = 140.26 (Bassett et al., 1991).
• Catholic Undergraduate Students: Mean = 128.45 (Bassett et al., 1991).

Permissions & Fee and Test Year

The Spiritual Maturity Index was originally developed in 1984 by Dr. Craig W. Ellison at Alliance Theological Seminary in Nyack, New York. The scale was disseminated primarily through unpublished research manuscripts, doctoral dissertations, and academic validation articles. No commercial test manual or proprietary licensing fee was ever formally instituted. Dr. Ellison historically permitted open academic and pastoral use of the scale for non-commercial educational and empirical research purposes. Researchers wishing to utilize the instrument in scholarly studies may reproduce the 30 items with appropriate academic attribution to Ellison (1984).

References

Barker, G., DeWitt, J., Godwin, A., & Spotts, S. (1987). A construct validity study of the SMI: A systematic replication (Unpublished master’s thesis). Western Conservative Baptist Seminary, Portland, OR.

Bassett, R. L., Camplin, W., Humphrey, D., Dorr, C., Biggs, S., Distaffen, R., Doxtator, I., Flaherty, M., Hunsberger, P., Poage, R., & Thompson, H. (1991). Measuring Christian maturity: A comparison of several scales. Journal of Psychology and Theology, 19(1), 84–93. https://doi.org/10.1177/009164719101900109

Boliou, N. (1988). Spiritual maturity: A review of construct and research (Unpublished manuscript). Western Conservative Baptist Seminary, Portland, OR.

Boliou, N., Chapman, S., & Davis, K. (1987). An empirical examination of the Spiritual Maturity Index and Spiritual Well-being Scale in an Evangelical church population (Unpublished master’s thesis). Western Conservative Baptist Seminary, Portland, OR.

Bressem, M. R. (1986). The relationship between individual differences in imaginal abilities, Christian imaginal frequency, and Christian spirituality (Doctoral dissertation, Western Conservative Baptist Seminary). Dissertation Abstracts International, 48(12), 3714B.

Bufford, R. K. (1984, April). Empirical correlates of Spiritual Well-Being and Spiritual Maturity Scales. Paper presented at the annual meeting of the Christian Association for Psychological Studies, Dallas, TX.

Buhrow, W., Calkins, P., Haws, J., & Rost, K. (1987). The Spiritual Maturity Index: A study of reliability and validity (Unpublished research report). Alliance Theological Seminary, Nyack, NY.

Colwell, J. C. (1986). A correlational study of self-concept and spirituality in seminarians (Doctoral dissertation, Western Conservative Baptist Seminary). Dissertation Abstracts International, 47(11), 4645B.

Cooper, R. L. (1987). An empirical examination of the construct validity of the Spiritual Maturity Index. Dissertation Abstracts International, 47(11), 4645B. (UMI No. 87-04712).

Davis, W., Longfellow, D., Moody, A., & Moynihan, W. (1987). Spiritual Maturity Index: Construct validation (Unpublished master’s thesis). Western Conservative Baptist Seminary, Portland, OR.

Ellison, C. W. (1984). Personality, religious orientation, and spiritual well-being (Unpublished manuscript). Alliance Theological Seminary, Nyack, NY.

Gorsuch, R. L. (1984). Measurement: The boon and bane of investigating religion. American Psychologist, 39(3), 228–236. https://doi.org/10.1037/0003-066X.39.3.228

Mack, K., Stone, K., Renfroe, W., & Lloyd, K. (1987). Spiritual well-being and maturity construct (Unpublished master’s thesis). Western Conservative Baptist Seminary, Portland, OR.

McPherson, S. E. (1990). Studies in optimal religious functioning, personality traits, religious orientation, and spiritual maturity (Doctoral dissertation, Fuller Theological Seminary). Dissertation Abstracts International, 49(12), 3757A.

Pramann, R. F., Jr. (1987). Commitment to spouse and God: The relationship among measures of marital commitment and spiritual maturity (Doctoral dissertation, Western Conservative Baptist Seminary). Dissertation Abstracts International, 48(12), 3717B.

Items of the Scale