Luke 15:1-10 (ESV)
The Parable of the Lost Sheep
15:1 Now the tax collectors and sinners were all drawing near to hear him. 2 And the Pharisees and the scribes grumbled, 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 has lost one of them, does not leave the ninety-nine in the open country, and go after the one that 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 his 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.
The Parable of the Lost Coin
8 “Or what woman, having ten silver coins,  if she loses one coin, does not light a lamp and sweep the house and seek diligently until she finds it? 9 And when she has found it, she calls together her friends and neighbors, saying, ‘Rejoice with me, for I have found the coin that I had lost.’ 10 Just so, I tell you, there is joy before the angels of God over one sinner who repents.”