The Israelites went to Moses, and said, We have sinned, for we have spoken against the Lord, and against thee; pray unto the Lord, that he take away the serpents from us.

And Moses prayed for the people.

Isn't it amazing how quickly they got a revelation that they had sinned. One minute they were complaining about him and the next they are asking him to pray for them.

God not only forgave them but healed them also.