Albert Barnes' Notes on the Whole Bible - Jonah 3:5
And the people of Nineveh believed God; - strictly, “believed in God.” To “believe in God” expresses more heart-belief, than to “believe God” in itself need convey. To believe God is to believe what God says, to be true; “to believe in” or “on God” expresses not belief only, but that belief resting in God, trusting itself and all its concerns with Him. It combines hope and trust with faith, and love too, since, without love, there cannot be trust. They believed then the preaching of Jonah, and... read more
The Pulpit Commentary - Jonah 3:5-9
Jonah's successful ministry in Nineveh. With a quick and marvellous success was Jonah's ministry crowned. Doubtless the Ninevites knew how he had sought to escape his mission to them, and all the perilous and miraculous consequences of his flight. This seems clearly implied in our Lord's words, who says that Jonah was "a sign unto the Ninevites." And he only could be this in so far as they were acquainted with his history. He was "a sign" that Jehovah was not to be trifled with. If he, a ... read more