Cyril of Alexandria

But since the Jews are frequently reproved in holy Scripture for their many crimes, how agree with this people the words of the elder son, saying, Lo, these many years do I serve thee, neither transgressed I at any time thy commandment. (Jer. 2:5, Isa. 29:13.) This then is the meaning of the parable. The Pharisees and Scribes reproved Him because He received sinners; He set forth the parable in which He calls God the man who is the father of the two sons, (that is, the righteous and the sinners,) of whom the first degree is of the righteous who follow righteousness from the beginning, the second is of those men who are brought back by repentance to righteousness.