At that time faith ruled in the fathers, and also faith in this article (Gen. 1:28): “Be fruitful and multiply.” In our age, especially after those papistic monstrosities of celibacy, marriage has been deprived of its prestige and due honor, and true knowledge of the Word and ordinance of God has become extinct. Among the fathers this knowledge was pure and proper. For this reason they had a very high regard for the begetting of children.

Luther on Genesis 25 (AE 3)