The descent of rain is subject to natural causes and conditions on the one hand, and in religious teachings is linked to divine will and certain human actions on the other. Thus, the question arises whether an act of worship like the rain prayer can have a creative and non-independent role, and whether this can be explained within Islamic philosophy. The present study, using a descriptive-analytical method and relying on Islamic philosophical and theological foundations, assesses the philosophical and theological possibility of the rain prayer's effect on rainfall and explains the theoretical path of this connection. Findings show that based on longitudinal causality, the principle of congruence, the levels of existence, mediation between worlds, the influence of the perfected soul, and the inner effects of actions, the connection between the devotional act and the natural phenomenon is not philosophically or theologically incompatible with the causal and monotheistic system. Thus, if these foundations are accepted and appropriate causal intermediaries are established, the rain prayer can be conceived as having a preparatory and non-independent role in a longitudinal chain of the devotional act, psychological and spiritual effects, meta-material levels, and a possible connection with material causes of rainfall. However, these foundations only explain the metaphysical possibility of such a connection and do not prove its external and empirical occurrence. Therefore, the effect of the rain prayer on rainfall is theoretically conceivable and explicable within the examined philosophical and theological framework.