Matthew 18:10-14 - The Parable Of The Lost Sheep
10 "See that you do not despise one of these little ones. For I tell you that in heaven their angels always see the face of my Father who is in heaven. 11 (...) 12 What do you think? If a man has a hundred sheep, and one of them has gone astray, does he not leave the ninety-nine and go to the mountains in search of the one that went astray? 13 And if he finds it, truly, I say to you, he rejoices more over that sheep than over the ninety-nine that did not go astray. 14 So it is not the will of your Father who is in heaven that one of these little ones should perish.
1 Now the tax collectors and sinners were all drawing near to hear him. 2 And the Pharisees and the scribes murmured, saying, "This man receives sinners and eats with them."
3 So he told them this parable: 4 "What man of you, having a hundred sheep, if he loses one of them, does not leave the ninety-nine in the wilderness, and go after the one which is lost until he finds it? 5 And when he has found it, he lays it on his shoulders, rejoicing. 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 which was lost.' 7 I tell you that in the same way there will be more joy in heaven over one sinner who repents than over ninety-nine righteous persons who need no repentance.