Continuing the theme of redemption, Jehovah acknowledges that He had allowed hard times to come upon them, but yet he will keep His covenant with them. He reminds his people that after the destruction of the great flood, he promised that he would not do so again. While it is easy for us to apply that universal flood to universal humankind, for Israel, it was their ancestor who was saved from the destruction, and the promise was given to them.
Thus, this image reinforces the declaration that God has not forgotten them, even in their trials.