Charles Spurgeon Commentary Jeremiah 4:10

"Then said I, Ah, Lord Jehovah! surely thou hast greatly deceived this people and Jerusalem, saying, Ye shall have peace; whereas the sword reacheth unto the life." — Jeremiah 4:10 (ASV)

God promises them peace, but it was on a condition which they did not fulfill. There was peace while they gave up their sin, but There is no peace, With God, unto the wicked; and so they missed it.