lost sheep, lost coin, prodigal son-the lost coin and prodigal son are only found in the gospel of Luke-these stories are here because of how religious leaders were appalled that jesus associated with tax collectors and sinners.
we must understand that misery is associated with careless living God has a design for our lives. remember the younger brother is a jew and he just blows all of his inheritance and now a JEW is tending pigs…no jew would have anything to do with pigs if all possible because is anything is unclean its pigs…personally I am glad the new covenant allows us to be able to eat pork. but he had no other choice and he couldn’t even eat what pigs had which was pods from the carob tree…used for animal food. think of corn husks.
i think the important idea for this parable is this that God loves sinners to restore them to be able to have a relationship with him.