Then Israel sang this song
 Being affected with the free favour and good will of God towards them: 
 spring up, O well;
 for the springing up of which they prayed in faith, believing in the promise of God, that it would spring up; and so encouraged one another not only to believe it, but even to sing on account of it before it actually did: 
 sing ye unto it;
 or on account of it praise the Lord for it; or "answer to it" F13, it being their manner to sing their songs by responses, or alternately.