Luke 15:3-7

3 So he told them this parable:
4 "If one of you has a hundred sheep and loses one of them, doesn't he leave the other ninety-nine in the desert and go after the lost one until he finds it?
5 When he does find it, he joyfully hoists it onto his shoulders;
6 and when he gets home, he calls his friends and neighbors together and says, `Come, celebrate with me, because I have found my lost sheep!'
7 I tell you that in the same way, there will be more joy in heaven over one sinner who turns to God from his sins than over ninety-nine righteous people who have no need to repent.