Luke 15:11 - Albert Barnes' Notes on the Bible

And he said - Jesus, to illustrate still farther the sentiment which he had uttered, and to show that it was proper to rejoice over repenting sinners, proceeds to show it by a most beautiful and instructive parable. We shall see its beauty and propriety by remembering that the “design” of it was simply to “justify his conduct in receiving sinners,” and to show that to rejoice over their return was proper. This he shows by the feelings of a “father” rejoicing over the “return” of an ungrateful and dissipated son.