Jesus lays out two parables in the first part of Luke 15: the parable of the lost sheep, and the parable of the lost coin. In each of these, we see two defining issues: Something is not where it is supposed to be, and God diligently seeks to restore it to its rightful place.
In the case of the lost sheep, we see a representative of someone who has wandered away from God, who is no longer in fellowship and is not receiving the benefits of God’s grace and care. We see God’s urgency in restoring that soul – an urgency that leads the shepherd in the parable to leave the other 99 sheep in the open field, and go bring back the lost sheep. The shepherd does this because he cares about the well-being of the sheep.
In the case of the lost coin, we see a woman searching for what represented approximately one day’s wages. The emphasis in this parable is on the value of that coin – the owner of the house doesn’t see a valueless object that can be easily replaced, and understands that even though the object is safely in the house, it still has no real value until it is found and available for use. So too, God sees his people as individuals with worth, valuable assets in the kingdom.
These parables set up the third story in the chapter: the Prodigal Son. Here the focus is on the father’s love, showing God as desiring His creation’s return just as a father seeks his child. But Jesus uses this story to highlight the issue with the religious leaders of the day, who would have seen the younger son as getting his just desserts, behaving in a way that we will would all term selfish, ungrateful, and sinful in nature. But when the brother turns and comes home, the father’s admonition to the older brother is: “It was fitting for us to celebrate!” And in the same way, God wants His children to love each other, and seek each other’s salvation with just as much urgency and zeal as He seeks it.