The Parable of the Lost Sheep

Matthew 18.12-14
12 What do you think? If a shepherd has a hundred sheep, and one of them has gone astray, does he not leave the ninety-nine on the mountains and go in search of the one that went astray? 13 And if he finds it, truly I tell you, he rejoices over it more than over the ninety-nine that never went astray. 14 So it is not the will of your Father in heaven that one of these little ones should be lost.

Luke 15.3-7
3 So he told them this parable: 4 "Which one of you, having a hundred sheep and losing one of them, does not leave the ninety-nine in the wilderness and go after the one that is lost until he finds it? 5 When he has found it, he lays it on his shoulders and rejoices. 6 And when he comes home, he calls together his friends and neighbors, saying to them, 'Rejoice with me, for I have found my sheep that was lost.' 7 Just so, I tell you, there will be more joy in heaven over one sinner who repents than over ninety-nine righteous persons who need no repentance.