Spiritual Maturity Index

Abstract

The Spiritual Maturity Index (SMI) is a 30-item, self-report instrument designed to measure the construct of Spiritual Maturity as a continuous developmental process within the framework of evangelical Christian theology. The scale utilizes a 6-point Likert-style format, ranging from “strongly agree” (SA) to “strongly disagree” (SD). Twelve of the items are reverse-scored to mitigate potential response bias resulting from negative wording. Items were logically derived from the conceptualization developed by Craig W. Ellison (1984), resulting in high face validity.

The SMI is easily self-administered, typically taking less than 10 minutes to complete. The total score is calculated by summing the scores of all items, resulting in a score range of 30 to 180, where higher scores indicate greater spiritual maturity. Although the instrument does not include specific items to check for social desirability or other response biases, the instructions attempt to diffuse this tendency by explicitly stating that there is no “right” answer.

Keywords

Spiritual Maturity Index, SMI, religious maturity, Christian spirituality, evangelical theology, self-reflection, autonomy, Likert scale, spiritual well-being.

Authors

Craig W. Ellison

Purpose

The primary purpose of the Spiritual Maturity Index (SMI) is to provide a comprehensive, quantitative measure of religious maturity. It was specifically developed to assess the developmental progress of individuals along a continuum of spiritual growth, drawing its theoretical foundation directly from evangelical Christian theological concepts.

The scale aims to identify and quantify the attitudinal and behavioral criteria associated with mature faith. It is intended for use primarily in research settings within religious or educational institutions where the assessment of Christian spiritual health and development is relevant, although its broad application is currently limited by a lack of standardization and a formal manual.

Construct

The SMI measures spiritual maturity, which its originator, Craig W. Ellison (1984), defines as a continuous developmental process marked by qualities similar to psychological maturity. The construct emphasizes the transition from external dependence to internal autonomy in faith.

Key components of the spiritually mature person include autonomy (faith beliefs are not solely dependent on the consensus of others), keen perception of reality, and creativity in everyday life. The mature individual engages in critical self-reflection to develop and maintain beliefs. Furthermore, maturity reflects interdependence alongside a strong sense of self, encompassing a willingness to make sacrifices for others and the ability to cope effectively with suffering. Spiritually mature individuals define their personal identity through closeness and communion with God, prioritize regular devotional time, and actively express classic Christian virtues and disciplines.

Validity

The scale demonstrates high face validity, as the items were logically derived and directly correspond to Ellison’s conceptualization of spiritual maturity. However, empirical research has raised questions regarding construct validity, particularly concerning the scale’s distinctiveness from related measures.

Research has consistently shown moderately significant correlations between the SMI and Ellison’s Spiritual Well-Being Scale (SWBS) (e.g., r = .57, p = .001 in Ellison, 1984; r = .62 in Bufford, 1984). Although the relationship was initially hypothesized to measure different aspects of spiritual health, these strong correlations suggest that the SMI may not measure a discrete dimension separate from the SWBS. This overlap suggests that the construct validity of the SMI, as a unique measure, appears weak.

Known-groups studies (Buhrow et al., 1987) offered modest support, successfully discriminating between those who profess Christ as Savior versus those who only follow Christ’s teachings. However, researchers recommend further studies on criterion-related and content validity, along with greater heterogeneity in samples, to fully establish the measure’s utility and strengthen its theoretical foundation.

Reliability

The Spiritual Maturity Index exhibits strong internal consistency across multiple studies. The internal consistency coefficient, calculated using Cronbach’s alpha, was reported as .87 by Buhrow et al. (1987) among a seminarian sample. Bassett et al. (1991) subsequently reported an even higher value of .92, confirming the measure’s reliability regarding the homogeneity of its items.

While Buhrow et al. (1987) attempted to assess temporal stability by retesting a portion of their initial sample after six months, no specific results or correlation coefficients for test-retest reliability were reported in the available source content.

Factor Analysis

Several factor analytic studies conducted on the SMI have consistently yielded a single dominant factor. This factor accounts for a substantial amount of the variance within the scale, suggesting that the SMI primarily measures a unified, general dimension of spiritual commitment.

For example, Bassett et al. (1991) combined items from the SMI and the SWBS and found confirmation of a single factor that appeared to measure “the extent to which personal commitment was manifested in belief.” This finding aligns with the broader observation (Gorsuch, 1984) that many religious measures tend to tap into a general factor of religiosity rather than assessing multiple, discrete dimensions.

Instrument

Test Type: Self-report psychological scale

Format: 30 items, 6-point Likert-style format (Strongly Agree to Strongly Disagree)

Language Available: English (Original)

Population Group: Christian adults and students (samples included Sunday School attendees, seminary students, and Catholic and Protestant college students).

Age Group: Adult

Population Details: Standardization is currently lacking. Early research samples were restricted in heterogeneity, including 319 adult Sunday School attendees (Mack et al., 1987), 117 seminary students (Buhrow et al., 1987), and 215 college students (Bassett et al., 1991). Formal norms have not been established to aid in score interpretation.

Test Methodology: Self-administered questionnaire, completed in approximately 10 minutes. Items are scored 1 to 6, with 6 representing the most favorable direction (maturity). The total score is the sum of all item scores, ranging from 30 to 180. Instructions attempt to mitigate social desirability by emphasizing the confidentiality and lack of a “right” answer.

Keywords

Craig W. Ellison, Cronbach’s alpha, psychometrics, religiosity, spiritual growth, self-report measure, evangelical Christianity, factor analytic studies.

Authors

Author ORCID Identifier: Not provided in source content.

Affiliation Email addresses: Not provided in source content.

Correspondence Address: Craig W. Ellison, Ph.D., Alliance Theological Seminary, South Highland Avenue, Nyack, New York 10960

Permissions & Fee and Test Year

The Spiritual Maturity Index was developed by Craig W. Ellison in 1984. No formal manual is currently available for public distribution, making it difficult to confidently administer, score, or interpret the measure for a wide variety of applications. Researchers must obtain the instrument directly from the author for use.

Reference’s

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

Bassett, R., 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.

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 manuscript, 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. (1984). Empirical correlates of Spiritual Well-Being and Spiritual Maturity Scales. Paper presented at the 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 manuscript, 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, 47-1/, 4645B.

Cooper, R. L. (1987). An empirical examination of the construct validity of the Spiritual Maturity Index. Dissertation Abstracts International, 47, 4645B. (University Microfilms International, 87-04712)

Davis, W., Longfellow, D., Moody, A., & Moynihan, W. (1987). Spiritual Maturity Index: Construct Validation. Unpublished manuscript, 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, 228-236.

Mack, K., Stone, K., Renfroe, W., & Lloyd, K. (1987). Spiritual well-being and maturity construct. Unpublished manuscript, 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, School of Psychology). 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 SPIRITUAL MATURITY INDEX

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

Instructions: Please circle the choice that best indicates the extent of your agreement or disagreement with each of the following statements. Please note that there is no “right” response; your response should honestly describe your personal experience. Do not choose an answer that would make you look “spiritual” if it is not true of yourself. All responses will be confidential; please do not put your name on the questionnaire.

• SA = strongly agree
• MA= moderately agree
• A= agree
• D = disagree
• MD = moderately disagree
• D = strongly disagree

1. My faith doesn’t primarily depend on the formal church for its vitality.
2. The way I do things from day to day is often affected by my relationship with God.
3. I seldom find myself thinking about God and spiritual matters during each day. (R)
4. Even if the people around me opposed my Christian convictions, I would still hold fast to them.
5. The encouragement and example of other Christians is essential for me to keep on living for Jesus. (R)
6. I feel like I need to be open to consider new insights and truths about my faith.
7. I am convinced that the way I believe spiritually is the right way.
8. People that don’t believe the way that I do about spiritual truths are hard-hearted. (R)
9. I feel that a Christian needs to take care of his or her own needs first in order to help others. (R)
10. My faith doesn’t seem to give me a definite purpose in my daily life. (R)
11. I find that following Christ’s example of sacrificial love is one of my most important goals.
12. My identity (who I am) is determined more by my personal or professional situation than by my relationship with God. (R)
13. Walking closely with God is the greatest joy in my life.
14. I feel that identifying and using my spiritual gifts is not really important. (R)
15. I don’t seem to be able to live in such a way that my life is characterized by the fruits of the Spirit. (R)
16. When my life is done, I feel like only those things that I’ve done, as part of following Christ will matter.
17. I believe that God has used the most “negative” or difficult times in my life to draw me closer to Him.
18. I feel like God has let me down in some of the things that have happened to me. (R)
19. I have chosen to forego various gains when they have detracted from my spiritual witness or violated spiritual principles.
20. Giving myself to God regardless of what happens to me is my highest calling in my life.
21. I don’t regularly study the Bible in depth on my own. (R)
22. I actively look for opportunities to share my faith with non-Christians.
23. My relationships with others are guided by my desire to express the love of Christ.
24. I don’t regularly have times of deep communion with God in personal (private) prayer. (R)
25. More than anything else in life I want to know God intimately and to serve Him.
26. Worship and fellowship with other believers is a significant part of my Christian life.
27. It seems like I am experiencing more of God’s presence in my daily life than I have previously.
28. I feel like I am becoming more Christ-like.
29. I seem to have less consistent victories over temptation than I used to. (R)
30. On the whole, my relationship with God is alive and growing.

(R)-reversed-scored item