From Luther’s Lectures on Genesis in Luther’s Works
What, then, is the reason for this remarkable procreation?…But the theologians say, far more reliably, that these events take place through the working of the Word, because it is said here: “He blessed them and said: ‘Increase and multiply.’” This Word is present in the very body of the hen and in all living creatures; the heat with which the hen keeps her eggs warm is the result of the diving Word.
Moses’ terminology must again be noted. What he calls a blessing the philosophers call fertility, that is to say, a state in which sound and living bodies are brought forth by sound and living bodies…This is a great miracle; but, like the rest, so this one has also become commonplace through experience… So now we have the living creatures that were created on the fifth day…This Word is still effective and brings about these results” (1:53-54)
Adam was not to live without food, drink, and procreation. But at a predetermined time, after the number of saints had become full, these physical activities would have come to an end; and Adam, together with his descendants, would have been translated to the eternal and spiritual life. Nevertheless, these activities of physical life—like eating, drinking, procreating, etc.—would have been a service pleasing to God; we could also have rendered this service to God without the defect of the lust which is there now after sin, without any sin, and without the fear of death (1:56-57).
Be fruitful. This command of God added for the creature. But, good God, what has been lost for us here through sin! How blessed was that state of man in which the begetting of offspring was linked with the highest respect and wisdom, indeed with the knowledge of God! Now the flesh is so overwhelmed by the leprosy of lust that in the act of procreation the body becomes downright brutish and cannot beget in the knowledge of God.
Thus the power of procreation remained in the human race, but very much debased and even completely overwhelmed by the leprosy of lust, so that procreation is only slightly more moderate than that of the brutes. Added to this are the perils of pregnancy and of birth, the difficulty of feeding the offspring, and other endless evils, all of which point out to us the enormity of original sin. Therefore the blessing, which remains till now in nature, is, as it were, a cursed and debased blessing if you compare it with that first one; nevertheless, God established it and preserves it. So let us gratefully acknowledge this “marred blessing.” And let us keep in mind that the unavoidable leprosy of the flesh, which is nothing but disobedience and loathsomeness attached to bodies and minds, is the punishment of sin. Moreover, let us wait in hope for the death of this flesh that we may be set free from these loathsome conditions and may be restored even beyond the point of that first creation of Adam…
Here you see how solicitous God is for the man He has created. First He created the earth like a house in which he should live. Then He arranged the other things He regarded as necessary for life. Finally He gave the gift of procreation to the man He had created… (1:71-72)
Today you find many people who do not want to have children. Moreover, this callousness and inhuman attitude, which is worse than barbarous, is met with chiefly among the nobility and princes, who often refrain from marriage for this one single reason, that they might have no offspring. It is even more disgraceful that you find princes who allow themselves to be forced not to marry, for fear that the members of their house would increase beyond a definite limit. Surely such men deserve that their memory be blotted out from the land of the living. Who is there who would not detest these swinish monsters? But these facts too, serve to emphasize original sin. Otherwise we would marvel at procreation as the greatest work of God, and as a most outstanding gift we would honor it with the praises it deserves. 1:118-119).
After this beginning was made, there then follows the no less wonderful propagation through the union of a male and female, whereby the entire human race is brought into being from a droplet of the human body. In a similar vein Paul, on the basis of this passage, has a clever discourse among the philosophers in Athens…Here Paul is speaking of the propagation brought about by the first man when he says “from the blood of one man.” If, therefore, man is brought into existence from a droplet of blood, as the experience of all men on the entire earth bears witness, surely this is no less miraculous than that the first man was created from a clod, and the female from a rib of the man.
But why does the creation of Adam and Eve seem so unbelievable and miraculous, while man’s propagation, which all men know and see does not seem so miraculous? Undoubtedly because, as Augustine says, miracles become commonplace through their continuous recurrence… (1:125).
Saintly women have always regarded childbirth as a great sign of grace. Rachel is rude and exceedingly irksome to her husband when she says (Gen. 30:1): “Give me children, or I shall die!” She makes it clear that she will die of grief because she sees that barrenness is a sign of wrath. And in Ps. 127:3 there is a glorious eulogy of offspring: “Lo, sons are a heritage from the Lord, the fruit of the womb a reward [that is, a gift of God].” Surely it is a magnificent name that children are the gift of God! Therefore Hannah laments so pitiably (1 Sam. 1:10), and John’s aged mother Elizabeth leaps for joy and exults (Luke 1:25): “The Lord has taken away my reproach.”
Thus when the world was still in a better state, barrenness was considered a sign of wrath; but childbirth was considered a sign of grace. Because of the abuses of lust, however, this remnant of the divine blessing gradually began to be obscured even among the Jews, just as today you could find many greedy men who regard numerous offspring as a punishment.
Saintly mothers, however, have always regarded this gift—when they were prolific—as a great honor, just as, conversely, they have regarded barrenness as a sign of wrath and as a reproach.
Therefore when poor Sarah sees that she is barren, she is almost undone by this trial. No doubt godly Abraham often had to cheer her up with his comforting words. Thus her sex was condemned to be punished with pain, but the blessing was not completely taken away on this account.
The woman’s members were condemned to punishment, but they were not condemned to sterility. The same thing happened when the males were circumcised. The males are required to be circumcised, and through circumcision of the foreskin it is shown that their birth is cursed and full of sins. Yet there the comfort is added: “I am the Lord your God” (3:134).
Therefore the fact that Moses frequently brings God’s Word or promise into this account does not imply that our ordinary way of giving birth takes place without the Word. For when God once said (Gen. 1:28): “Be fruitful,” that Word is effective to this day and preserves nature in a miraculous way. But how few there are who believe this or are aware of it! (4:4).
But this is the true definition: Marriage is the divinely instituted and lawful union of a man and a woman in the hope of offspring, or at least for the sake of avoiding fornication and sin, to the glory of God. Its ultimate purpose is to obey God and to be a remedy for sin; to call upon God; to desire, love, and bring up children to the glory of God; to live with one’s wife in the fear of the Lord; and to bear one’s cross. But if no children result, you should nevertheless live content with your wife and avoid promiscuity (4:244).
And it seems that God wanted to teach and attest that the begetting of children is wonderfully pleasing to Him, in order that we might realize that He upholds and defends His Word when He says: “Be fruitful.” He is not hostile to children, as we are. Many of us do not seek to have offspring. But God emphasizes His Word to such an extent that He sometimes gives offspring even to those who do not desire it, yes, even hate it. It is His purpose to test them. And what is more, He seems to emphasize procreation to such an extent that children are born even to adulterers and fornicators contrary to their wish.
How great, therefore, the wickedness of human nature is! How many girls there are who prevent conception and kill and expel tender fetuses, although procreation is the work of God! Indeed, some spouses who marry and live together in a respectable manner have various ends in mind, but rarely children (4:304-305).
For one must consider that at that time fertility was regarded as an extraordinary blessing and a special gift of God, as is clear from Deut. 28:4, where Moses numbers fertility among the blessings. “There will not be a barren woman among you,” he says (cf. Ex. 23:26). We do not regard this so highly today. Although we like and desire it in cattle, yet in the human race there are few who regard a woman’s fertility as a blessing. Indeed, there are many who have an aversion for it and regard sterility as a special blessing. Surely this is also contrary to nature. Much less is it pious and saintly. For this affection has been implanted by God in man’s nature, so that it desires its increase and multiplication. Accordingly, it is inhuman and godless to have a loathing for offspring. Thus someone recently called his wife a sow, since she gave birth rather often. The good-for-nothing and impure fellow! The saintly fathers did not feel like this at all; for they acknowledged a fruitful wife as a special blessing of God and, on the other hand, regarded sterility as a curse. And this judgment flowed from the Word of God in Gen. 1:28, where He said: “Be fruitful and multiply.” From this they understood that children are a gift of God (5:325).
But in the meantime states and the procreation and education of children remain, because the number of the elect has not yet been completed. Many of these have not yet been born. But when the number is completed, then let the pope and the Turk see what will become of them! (7:42).