If the LORD doesn't build a house, the work of its builders is useless. If the LORD doesn't watch over a city, it's useless for those on guard duty to stand watch over it.
References for Psalms 127:1
It's useless for you to work from early morning until late at night just to get food to eat. God provides for those he loves even while they sleep.
Children are a gift from the Lord. They are a reward from him.
Children who are born to people when they are young are like arrows in the hands of a soldier.
Blessed are those who have many children. They won't be put to shame when they go up against their enemies in court.