Rashi, on Ps 126:1

“Unless the Lord build the house, they labour in vain that build it. Unless the Lord keep the city, he watcheth in vain that keepeth it.”

“A song of ascents about Solomon This song David recited about his son, Solomon, for he saw through the holy spirit that he [Solomon] was destined to build the Temple, and on that very day, Solomon would marry Pharaoh’s daughter, and concerning this was said (Jer. 32:31): “For this city has aroused My anger and My wrath since the day they built it.” Therefore, he recited this song. My son, why should you build a house and turn away from following the Omnipresent? Since He does not desire it, its workers have toiled at it in vain. [its] watcher keeps his vigil in vain The watchman watches it in vain.”

Imported from an open dataset — not yet checked against the printed edition.