Psalm 127 likens children to arrows in the quiver of a warrior – in the hands of a mighty man, arrows are a powerful deterrent against enemies that come to attack a city. The New Living Translation puts it this way:
Children are a gift from the Lord; they are a reward from him. Children born to a young man are like arrows in a warrior’s hands. How joyful is the man whose quiver is full of them! He will not be put to shame when he confronts his accusers at the city gates” (Psalm 127:3-5).
The NLT Study Bible makes the following useful comments on these verses:
Children are one of God’s blessings. The words translated “children” (Hebrew ‘banim’) and “builders” (Hebrew ‘bonim’ in verse 1) forms a word-play. Having children builds a family. God uses children to protect the reputation of his people against the wicked.
Any parent will tell you that the older you get before you have children the more hard work it becomes. Young men and young women (who are old enough to marry and raise a family) are also more fertile and more likely to produce healthy offspring. The older you get, the more complications arise. Trust me, I know – been there and done that!
We should also take into consideration the realities of life thousands of years ago. Parents hoped that when they got old and became infirm their children would take care of them. Back then families formed strong bonds and parents expected that when their children grew up they would support them in old age.
The Teacher encourages a young man to enjoy his wife and to do all that he can while he has strength before old age overtakes him. He concludes:
Fear God and keep his commandments, for this is the whole duty of man. For God will bring every deed into judgment, including every hidden thing, whether it is good or evil (Ecclesiastes 12:13-14).
Psalm 127 is not advocating that teenagers start to procreate as soon as they are physically able. Raising a family brings responsibilities and should never be undertaken likely. Psalm 127 merely observes that having children is a blessing from God and that raising a family should bring joy to their parents.