What is the importance of procreation according to the Bible?

Moreover, the object of the oneness of man and wife, the inviolability of the marriage bond (save for the one sin specified by our Lord (Matt. 19) — the sin itself being, in fact, its violation) is declared by the prophet. "And wherefore one? That He might seek a godly seed." The Lord thus looks to find His people among the children of His servants; and it is on this account indeed that the apostle enjoins believing parents to bring up their children in the nurture and admonition of the Lord. The Lord's interest in, and His care and love for the children of His people, have not been sufficiently remembered, nor that the godliness of the children — "a godly seed" — is divinely connected with the maintenance of the indissoluble sanctity of the marriage relationship. We have even further light now, because the Lord has been pleased to show us that the union of husband and wife is a figure of that between Him and the Church, and hence our responsibility is the greater, both to understand the nature of marriage, and also God's attitude of grace and blessing towards the offspring of His saints.

How intimate the relationship. Taken out of man (Ish) she was called woman (Isha). Marriage is instituted for man and woman’s comfort and joy, and for the procreation of the human race. In Genesis 1 man and woman are exhorted to be fruitful and multiply and replenish the earth, to subdue it, to have dominion over it, Adam being head over all. A man is to leave his father and mother and cleave unto his wife, one in affection and interest, each the complement of the other.

Verse 27 states that duality characterizes man. It says that God created "him; male and female created He them." This fact is elaborated in Genesis 2, but the few words here show us how closely male and female are identified. The word, "man" covers both, and jointly they were to have the dominion, though the male from the outset was given the leading place. From the outset too they were blessed by God and bidden to multiply and replenish the earth. Before sin came in therefore children were in God's purpose for them.

Then again one can understand how favourable the lengthened span of life in those days was to carrying out God's word in blessing the first pair, Be fruitful, and multiply, and replenish the earth, and subdue it; and have dominion over fish of the sea, and over bird of the heavens, and over every living thing that moves upon the earth. Thus not only is the fact unquestionable for all that respect revelation, but the wisdom, not to say necessity, of that exceptional condition, is pretty apparent.

But to return, we read, "And God blessed them; and God said to them, Be fruitful, and multiply, and fill the earth, and subdue it; and have dominion over fish of the sea and bird of the heavens, and over every living thing that creeps on the earth" (ver. 28). Man, as Prof. Owen said, is the sole species of his genus, and the sole representative of his species.

This is the second benediction of creation. The first was when God made the creatures that peopled the waters and the air of Adam's world, the earliest to enjoy animal life in that state of things. God has pleasure in blessing His creatures that have a life even of a lowly kind to appreciate the fruits of His goodness, and especially in view of their reproduction and multiplying within their sphere. Here, a second time, He blessed mankind, male and female, of whom alone it is said, though the detailed difference is reserved for a subsequent and more fitting occasion. In verse 22 we have only "saying," but here "God said to them, Be fruitful," etc. Man was the depository of God's revelation, as he ought to be His priest, and, as we have seen, His viceroy. This is more than the interpreter of nature, as one of our sages styled him. He had intercourse with God at once.

Language thus was in no way the slow invention of man's wit, but an immediate endowment of our first parents by God from creation. Here His word assures us of its reality from the first day of man's creation; and everything confirms in the chapters that follow. To imagine otherwise is to disbelieve the Bible and prefer one's own thoughts or the dreams of other men, as if we or they could know anything about the matter. He Who alone knows all has been pleased to tell us the truth through Moses. His word was valid for the unintelligent creation: how comforting for the human pair to hear Him say, Be fruitful, and multiply, and fill the earth and subdue it! Even though man comes in as a creature with the rest, still he is introduced exceptionally as the crown of creation; and the higher creatures are pronounced good separately from man, who is blessed, male and female, in an address to them as at the head of all the rest.

God then blessed them and told them, “Be fruitful and multiply, and fill the earth and subdue it; and rule over the fish of the sea and over the birds of the sky, and over every living thing that moves on the earth.” This was said before sin entered the scene. Some have claimed that sexual union is sinful, but this is true only outside the marriage bond. At this time Adam and Eve were to rule over other animate creatures. By sin they spoiled this, so that man does not now have the same authority over animals, though Noah was told, “the fear of you and the dread of you shall be upon every beast” etc. (Gen. 9:2). This is a mercy of God, for otherwise animals could take terrible advantage of their superior strength to terrorize men.

What of Solomon’s son, his successor on the throne? The unequal yoke is not only the question of marriage, serious as that is, but there is the question of a family. In marriage this is generally looked forward to. “Lo, children are an heritage of the Lord: and the fruit of the womb is His reward” (Ps. 127:3). Marriage sets in train a good deal that passes beyond our control, and may be bearing fruit generations after we have passed out of this world.

David proclaimed, "Lo, children are an heritage of Jehovah: and the fruit of the womb is his reward." Ps. 127:3. Women in the East had a great desire for children, as may be seen by Sarah, Rachel, and Leah giving their handmaids to their husbands that they might have children by them, and this ever characterised the women of Israel afterwards.

The last three verses go together, and complete the subject of the Psalm. Thus we have the dwelling, taking now the house in its primary significance; then, guardian care with repose of spirit; and lastly, the family — the children. But if there be children, they also are God's gift — an heritage of (from) the Lord; and they are His gift as His recompense or reward, as the mark of His approval and blessing bestowed on those who fear Him and walk in obedience to His word, according to His promise to His earthly people. (See Deuteronomy 28:11, and the next Psalm.) We see, therefore, that in every dispensation God will have His people learn that He is the source of all their blessings, that He is a GIVER, the God of all grace; and hence that the secret of a happy, restful life lies in realized dependence upon Himself. What anxieties and apprehensions we should be spared if this lesson were but more deeply graven upon our hearts! We then, indeed, might be careful for nothing, because we should only wait upon God, and have our expectation from Him, in the assurance that we could not obtain one single thing by our own efforts, however diligent, but that all must be received as God's gift. When we have once learned that God is a giver, we are content and happy to be receivers.

A numerous progeny are distinctly God's gift: happy the man that has his quiver full of them (Psalm 128). The blessings spoken of are declared to be the portion of whoever fears Jehovah. It is present temporal blessing — blessings out of Zion; and, the desire of the godly's heart, Jerusalem in prosperity all their days. Although the direct object be the remnant, the godly Gentile, so fearing Jehovah, owning Israel's God, would, as a principle, enjoy the blessing, and rejoice with His people.