Human societies have always utilized all available resources to achieve increasing progress and to attain peace and comfort; to achieve this peace in all arenas—medical, economic, and security—they require a sufficient population. Therefore, studying the issue of population is essential to facilitate more accurate decision-making in accordance with the Holy Sharia of Islam, and to clarify the matter through a thorough and comprehensive examination, focusing on all verses and narrations that can be influential and guiding in determining jurisprudential rulings or understanding the perspective of the Divine Lawgiver regarding the issue of population growth. The causes of population decline—including pessimism regarding marriage, extravagance in wedding ceremonies, general population reduction policies, and lifestyle changes—have been addressed. This article, compiled using descriptive and library research methods, outlines the damages of population decline, such as the catastrophe of reduced marriage rates and birth control, decreased social vitality, the decline of human capital and the active workforce, reduced social interactions, and diminished political authority. Regarding jurisprudential solutions to combat population decline, it addresses the true philosophy of marriage, procreation, the impermissibility of *azl* (coitus interruptus), the prohibition of abortion, and the abhorrence of divorce.