Augustine of Hippo
Catena Aurea · Lukasevangelium 15
Either what woman having ten pieces of silver, if she lose one piece, doth not light a candle, and sweep the house, and seek diligently till she find it? And when she hath found it, she calleth her friends and her neighbours together, saying, Rejoice with me; for I have found the piece which I had lost. Likewise, I say unto you, there is joy in the presence of the angels of God over one sinner that repenteth.
(de Quæst. Ev. lib. 2. qu. 33.) Or by the nine pieces of silver, as by the ninety and nine sheep, He represents those who trusting in themselves, prefer themselves to sinners returning to salvation. For there is one wanting to nine to make it ten, and to ninety-nine to make it a hundred. To one He assigns all who are reconciled by repentance.