Albert Barnes Commentary Jeremiah 29:4-7

"Thus saith Jehovah of hosts, the God of Israel, unto all the captivity, whom I have caused to be carried away captive from Jerusalem unto Babylon: Build ye houses, and dwell in them; and plant gardens, and eat the fruit of them. Take ye wives, and beget sons and daughters; and take wives for your sons, and give your daughters to husbands, that they may bear sons and daughters; and multiply ye there, and be not diminished. And seek the peace of the city whither I have caused you to be carried away captive, and pray unto Jehovah for it; for in the peace thereof shall ye have peace." — Jeremiah 29:4-7 (ASV)

As the exile was God’s doing for their good, they were to make the best of their position and acquire wealth and influence; whereas if they were always restlessly looking out for the opportunity of returning home, they would rapidly fall into poverty and dwindle away.

Seek the peace of the city ... (Jeremiah 29:7) — this was not only because their welfare for seventy years was bound up with that of Babylon, but because it would have degraded their whole moral nature to have lived as conspirators, banded together against the country that was for the time their home.