John Gill Commentary 1 Kings 22:12

"And all the prophets prophesied so, saying, Go up to Ramoth-gilead, and prosper; for Jehovah will deliver it into the hand of the king." — 1 Kings 22:12 (ASV)

And all the prophets prophesied so, saying, go up to Ramothgilead, and prosper All encouraged the king to go up against this place, and prophesied of victory, as Zedekiah did:

for the Lord shall deliver it into the king's hand, (See Gill on 1 Kings 22:6).