Allegory is common in the Old Testament, and parables are a typical rabbinical method of teaching. The older son would have the first share in the father's inheritance as his firstborn, unless his younger brother received this share from the father by redemption via presentation in the temple. In addition, the younger son would receive the older son's inheritance upon his brother's death according to the mitzvah yibbum. The younger son demanding his share in his father's inheritance before his father's or his brother's death is illegal, as it is the same as assuming they are both dead. In this parable, Jesus portrays the younger son's life of sin in a typical scriptural way: sexual immorality, like how God describes Israel as a harlot to Hosea. Again, Jesus uses a typical scriptural way of describing the consequences of sin: bondage to wicked gentiles, like the Babylonian captivity. The younger son being joyfully greeted and celebrated by the father is typical of God promising to deliver Israel from exile. The older son not sharing in his father's joy is typical of scriptural portrayals of unrepentant sinners. The last few verses of the parable summarize the parable in accordance with the Jewish teaching of the two ways of acting: the way of life (obedience) and the way of death (sin). God, according to Judaism, rejoices over and grants more graces to repentant sinners than righteous souls who don't need repentance. With all this in mind, it is obvious what Jesus is implying with the parable: more than just teaching the Jewish leaders to rejoice as he does over repentant sinners, he is teaching them how Israel (firstborn son of God) ought to treat the righteous gentiles (son of Abraham according to God's promise to him). In addition, Jesus is teaching them that, if they do not repent of being prodigal sons, they will forfeit their inheritance, and so, not share in the world to come like the righteous gentiles.