Throughout the book of Luke we see Jesus spending time with sinners which the religious leaders f his day criticized Him often. In Luke 15, Jesus tells two stories to show why He associated with sinners. The first is about a lost sheep and the second about a lost coin. From these stories Jesus reveals three reasons why He hung out with sinners.
First, Jesus hung out with sinners because they were lost and very valuable to Him. The sheep was lost and very valuable to the shepherd. The coin was lost and very valuable to the woman. People are lost and very valuable to God.
Second, Jesus associated with lost people because He is willing to go through infinite trouble to find lost people. The shepherd was willing to do this to find the lost sheep as was the woman to find the lost coin. Jesus was willing to go through the trouble of the cross to find lost people.
Finally, Jesus spent time with sinners because nothing brings more joy to the portals of heaven then when a lost person becomes found. The shepherd rejoiced with his friends when the sheep was found. The women rejoiced with her friends when the coin was found. In the same way, every time someone repents and comes to Christ, heaven rejoices.