Charles Spurgeon Commentary Jeremiah 3:23

"Truly in vain is [the help that is looked for] from the hills, the tumult on the mountains: truly in Jehovah our God is the salvation of Israel." — Jeremiah 3:23 (ASV)

Truly in vain is salvation hoped for from the hills, and from the multitude of mountains:

See, they were trying to get it from their high places. They lifted up their voices to their gods, but they only learned to mourn and weep. In vain is salvation hoped for from the hills and from the multitude of mountains.