28 Then God blessed them, and God said to them, “Be fruitful and multiply; fill the earth and subdue it; have dominion over the fish of the sea, over the birds of the air, and over every living thing that moves on the earth.”
2 But Abram said, “Lord GOD, what will You give me, seeing I go childless, and the heir of my house is Eliezer of Damascus?” 3 Then Abram said, “Look, You have given me no offspring; indeed one born in my house is my heir!”
4 And behold, the word of the LORD came to him, saying, “This one shall not be your heir, but one who will come from your own body shall be your heir.” 5 Then He brought him outside and said, “Look now toward heaven, and count the stars if you are able to number them.” And He said to him, “So shall your descendants be.”
5 No longer shall your name be called Abram, but your name shall be Abraham; for I have made you a father of many nations.
60 And they blessed Rebekah and said to her:
“Our sister, may you become
The mother of thousands of ten thousands;
And may your descendants possess
The gates of those who hate them.”
5 And he lifted his eyes and saw the women and children, and said, “Who are these with you?”
So he said, “The children whom God has graciously given your servant.”
9 Joseph said to his father, “They are my sons, whom God has given me in this place.”
And he said, “Please bring them to me, and I will bless them.”
25 By the God of your father who will help you,
And by the Almighty who will bless you
With blessings of heaven above,
Blessings of the deep that lies beneath,
Blessings of the breasts and of the womb.
9 ‘For I will look on you favorably and make you fruitful, multiply you and confirm My covenant with you.
4 “Blessed shall be the fruit of your body, the produce of your ground and the increase of your herds, the increase of your cattle and the offspring of your flocks.
3 Then I took your father Abraham from the other side of the River, led him throughout all the land of Canaan, and multiplied his descendants and gave him Isaac.
38 He also blesses them, and they multiply greatly;
And He does not let their cattle decrease.
3 Behold, children are a heritage from the LORD,
The fruit of the womb is a reward.
4 Like arrows in the hand of a warrior,
So are the children of one’s youth.
5 Happy is the man who has his quiver full of them;
They shall not be ashamed,
But shall speak with their enemies in the gate.
3 Your wife shall be like a fruitful vine
In the very heart of your house,
Your children like olive plants
All around your table.
4 Behold, thus shall the man be blessed
Who fears the LORD.
5 The LORD bless you out of Zion,
And may you see the good of Jerusalem
All the days of your life.
6 Yes, may you see your children’s children.
Peace be upon Israel!
13 For He has strengthened the bars of your gates;
He has blessed your children within you.
18 Let your fountain be blessed,
And rejoice with the wife of your youth.
6 Children’s children are the crown of old men,
And the glory of children is their father.
Large Catechism, 4th Comm., # 105, Trigl. p. 611
"To this estate of fatherhood and motherhood God has given the special distinction above all estates that are beneath it that He not simply commands us to love our parents, but to honor them. .. He separates and distinguishes father and mother above all other persons on earth, and places them at His side."
Children are a blessing, the more the better! Family planning seeks to prevent and decrease the frequency and number of these blessings. Thus one shows contempt for God's blessings. Let us consider again Luther's words on this very point:
For one must also 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.
Luther's works, vol. 5, p. 329
"Although it is very easy to marry a wife, it is very difficult to support her along with the children and the household. Accordingly, no one notices this faith of Jacob. Indeed, many hate fertility in a wife for the sole reason that the offspring must be supported and brought up. For this is what they commonly say: “Why should I marry a wife when I am a pauper and a beggar? I would rather bear the burden of poverty alone and not load myself with misery and want.” But this blame is unjustly fastened on marriage and fruitfulness. Indeed, you are indicting your unbelief by distrusting God’s goodness, and you are bringing greater misery upon yourself by disparaging God’s blessing. For if you had trust in God’s grace and promises, you would undoubtedly be supported. But because you do not hope in the Lord, you will never prosper.
[Luther's works, vol. 5: Lectures on Genesis, page 332]
Also consider these words from the Luther's (Large Catechism) explanation of the First Commandment:
13] Thus you can easily understand what and how much this commandment requires, namely, that man's entire heart and all his confidence be placed in God alone, and in no one else. For to have God, you can easily perceive, is not to lay hold of Him with our hands or to put Him in a bag [as money], or to lock Him in a chest [as silver vessels]. 14] But to apprehend Him means when the heart lays hold of Him and clings to Him. 15] But to cling to Him with the heart is nothing else than to trust in Him entirely. For this reason He wishes to turn us away from everything else that exists outside of Him, and to draw us to Himself, namely, because He is the only eternal good.
26] For even though otherwise we experience much good from men, still whatever we receive by His command or arrangement is all received from God. For our parents, and all rulers, and every one besides with respect to his neighbor, have received from God the command that they should do us all manner of good, so that we receive these blessings not from them, but, through them, from God. For creatures are only the hands, channels, and means whereby God gives all things, as He gives to the mother breasts and milk to offer to her child, and corn and all manner of produce from the earth for nourishment, none of which blessings could be produced by any creature of itself.
27] Therefore no man should presume to take or give anything except as God has commanded, in order that it may be acknowledged as God's gift, and thanks may be rendered Him for it, as this commandment requires. On this account also these means of receiving good gifts through creatures are not to be rejected, neither should we in presumption seek other ways and means than God has commanded. For that would not be receiving from God, but seeking of ourselves.