Immediately after creating man and woman, God commanded them, “Be fruitful and multiply. Fill the land and conquer it” (Gen. 1:28).
One might think that the very first mitzvah in the Torah should be some central precept — not worshipping idols, for example, or belief in one God. What is so important about procreation, that this was God’s first command to humanity? And why was it necessary for God to command that which comes naturally to humans?
The fact that pru u'revu (procreation) is a mitzvah is central to Judaism’s worldview. This means that this activity is rooted in absolute holiness and goodness. Indeed, recognizing the holiness in procreation is the very basis for an ethical outlook.
If one is unable to perceive the absolute good that comes from the continued survival of the human race, then life itself is merely the lamentable triumph of our natural drives over the desire for good. Such a pessimistic view is the root of all negative traits and immoral behavior. The ultimate conclusion of such an outlook is that “Might makes right,” that the strong and the fit deserve to rule over the weak.
However, when procreation is revealed to us as a holy obligation, then we must acknowledge that our inner drive for the formation of life is not a blind biological instinct, but an expression of innate Divine goodness. This knowledge should impress upon us the inner goodness to be found in all aspects of life.
Nonetheless, we know that life is not easy. Life in this world is full of pain and suffering. The Sages concluded that it would better for the soul not to have been born (Eiruvin 13b). How can we bring children into such a world?
Just as this mitzvah reinforces our natural aspirations for goodness, so, too, it elevates our thoughts to recognize an underlying unity over time. The past, present, and future are all bound together. It is not for the flawed world of the present, nor the cruel world of the past, that we bear and raise children. Rather, we bring new souls into the world to advance the universe towards the infinitely bountiful world of the future.
Through the mitzvah of pru u'rvu, we actively participate in the world’s gradual progression. We help advance the universe to attain the lofty state when life will be revealed in its noblest form — when cognizant, sentient living beings will attain a state of incomparably refined and meaningful life. Humanity will experience a world in which life is no longer an onerous burden, but a precious gift and a wonderful blessing.
The Divine mandate of “Be fruitful and multiply, fill the world” demands that we perfect the world in all aspects. We are charged to advance the world, both physically and spiritually. We are commanded to “fill the world” both quantitatively and qualitatively.
We rise to this challenge when we overcome the harsh features of a raw and untamed world, through our efforts to settle and refine it.
(Adapted from Otzarot HaRe\'iyah vol. II, pp. 518-519)