Gregory of Nyssa — as excerpted in the Catena Aurea on Luke 15:1-7

“(Hom. de Mul. Pecc.) But when the shepherd had found the sheep, he did not punish it, he did not get it to the flock by driving it, but by placing it upon his shoulder, and carrying it gently, he united it to his flock. Hence it follows, And when he hath found it, he layeth it upon his shoulders rejoicing.”