The one who trusts in the Lord will, like the Psalmist, know the joys of fruitful labor and the delight of sweet rest. They will, Lord willing, know the rich blessing and heritage of an abundance of children, far greater than all other material blessings this earth has to offer. Such are the blessings when the Lord builds the house.
The culture in which we live is diametrically opposed to the idea of the family as set forth in Psalm 127. Here, the Psalmist refers to a household, composed of a father and mother who married early and are blessed by an abundance of children, as a direct and wonderful blessing from God.
It is, in fact, good for Christians to get married and have many children while young. It is an evil sign of modernity that family life is put off so long. Contra the opinions of secularism, children are not a burden but a blessing. Christians ought to desire a household full of offspring. After all, a household full of children is far greater and grander than a life without, no matter how Instagramable it may appear to onlookers. While it is true that, occasionally, God does not permit Christians to have children of their own, it is no less a good thing for young Christians to get married, have children, and strive toward filling a Christian household with godly, covenant children.
Of course, all such things are impossible apart from God. Building a house, like building a church, cannot be blessed if God is not laboring in the work himself. Solomon, whose inscription this Psalm bears, was a man who understood this well. His father, King David, had long desired to build a Temple for God to inhabit in a special way upon the earth. But God did not permit David to build such a House. The right to build went instead to his son, Solomon, and Solomon knew that the Lord’s blessing was essential to building both his own home and palace, and the Temple of the Lord.
Thus, verse 1 begins with the warning that, “Unless the Lord builds the house, those who build it labor in vain. Unless the Lord watches over the city, the watchman stays awake in vain.” While there are two ideas here, they are closely related. Just as it is essential for the Lord to build a house or the laboring is done in vain, so too must the Lord defend and protect a city, or the watchmen watches in vain. In other words, if the Lord does not build the house, it will crumble regardless of the materials used and craftsmanship employed.