In this chapter Jesus gives rise to two parables, which illustrate the love and concern of God for sinners, his attitude is totally opposed to those who believed themselves righteous.
The Pharisees correspond to the 99 sheep, the 9 coins and the older brother.
The publicans and sinners correspond to the lost sheep and the lost coin.
Both parables show us that God cares for the one who has been lost and rejoices with his recovery, those who in a legalistic way are considered righteous are not aware of their need.
The sheep are left unarmed and refuse to move, but when Jesus shares with sinners it is celebrated with joy, just as when a shepherd shares with his friends the joy of finding a lost sheep.
Our God is a God of eternal mercy!