What does Psalm 126:5 mean?

In ancient Israel, most people understood basic agriculture. They intuitively knew that land left alone for a long time would become difficult to cultivate. The context of this psalm seems to be the return of Israelites from seventy years of exile in Babylon (Ezra 2:1). To re-establish farms and vineyards would require intense work. These "tears" of effort and toil would result in the blessings of future harvests. This concept applies both to crops and to believers who tell others about the gospel (Galatians 6:9). Those who came back from captivity were trusting God to bless their efforts (Haggai 2:19; Psalm 126:4).

Some interpreters believe this part of the psalm speaks about bringing the rest of the displaced nation of Israel back to the Promised Land. Ancient historians indicate that when Israel was allowed to return after seventy years, most of them chose to stay—Babylon was their home. The psalmist may be yearning to see many more Israelites coming from exile. The struggle to rebuild farming and city structure in Israel would, hopefully, encourage these reluctant ones.