Adopting a rationalist approach, Maimonides (Mūsā b. Maymūn) elucidates the ultimate purpose (g̲h̲āya) of the rulings of the s̲h̲arīʿa primarily in terms of worldly benefits, encompassing both the moral reformation of the soul and the regulation of social relations. Although this functionalist interpretation represents a significant advancement in Jewish theology by explaining the rationality of rulings, this study—employing an analytical-critical method and drawing on the teleological and ontological foundations of Transcendent Philosophy (al-ḥikma al-mutaʿāliya)—argues that this approach suffers from a form of reductionism. The findings of this research indicate that by neglecting the ontological and existential dimensions of the human being, Maimonides has demoted the s̲h̲arīʿa from being a “path for the perfection (istikmāl) of the soul” and a means of “connection to the sacred realm” to a mere instrument for worldly well-being. Conversely, the philosophy of Mullā Ṣadrā, by demonstrating the ontological efficacy of acts of worship and the genuine nexus between the s̲h̲arīʿa and the degrees of existence (marātib al-wujūd), exposes the theological lacunae inherent in the functionalist interpretation. While critiquing the functionalist foundations of Maimonides’s thought, this study demonstrates how Ṣadr al-Mutaʾallihīn’s perspective on the ultimate purpose of the s̲h̲arīʿa—viewed not as a social instrument, but rather as a “catalyst for existential intensification(is̲h̲tidād)”—furnishes a more comprehensive paradigm for the philosophical explanation of religion.