Jesus continued with His teaching about not despising the 'little ones'. He was not just talking about children but also the adults who trusted Him and submitted to His authority … the 'children of His kingdom'. So He reinforced the teaching with this parable.
 
The imagery would have been easily understood in a farming economy. Sheep were living investments. They came to the owner of the flock without cost – they were born on his land. However they cost a lot of time and effort to raise them until their increased value could be realised when he sold them. Every animal which strayed was well worth searching for. A lost sheep would not only be at risk of death from wolves, but the farm owner would lose his investment.
 
No sensible shepherd would say it did not matter if his flock was diminished. Of course it mattered. Not so much as an issue of animal welfare as of rightful ownership. So the owner himself would keep looking for the animal until he found it. His successful rescue mission would be the cause of great joy; and a special bond would be formed with that sheep, more so than with the much larger group of compliant livestock. That is Father God's reaction too. God cares deeply about all the people born on His world and does not want any of them to perish (2 Peter 3:9). That is why Jesus came, to bring many children to enjoy God's glory (Hebrews 2:10): also to delight God as He establishes a relationship bond with them (Luke 15:7).
 
But note that this rescue is not described as being of benefit to the sheep, but for the benefit of Father God who regains real ownership of what belongs to Him. It is a common mistake to assume that God's salvation is primarily for the benefit of the saved. Yes, there is great benefit; but that is small compared to God's joy when He re-establishes His Lordship over His creation. Christians who merely revel in the blessings of salvation may be tempted to abuse the grace of God, but mature believers know they have been rescued at great cost and have an obligation to live in such a way that God is pleased (1 Corinthians 6:20).