In Luke 15, it is the first member of a trilogy about redemption that Jesus addresses to the Pharisees and religious leaders after they accuse him of welcoming and eating with "sinners.
Green writes that "these parables are fundamentally about God, ... their aim is to lay bare the nature of the divine response to the recovery of the lost.
The image of God rejoicing at the recovery of lost sinners contrasts with the criticism of the religious leaders which prompted the parable.
[2] Justus Knecht gives the typical Catholic interpretation of this parable, writing: By the simile of the Good Shepherd our Lord teaches us how great is His compassionate love for all mankind.
All men, Jews and Gentiles, are His sheep, and He gave His life for all, being sacrificed on the Cross to redeem them from sin and hell.
He knows all about them, their needs, their weakness, their thoughts, their endeavours; He leads them into the fold of His Church, He helps them by His grace, He enlightens them by His doctrine, and nourishes and strengthens them with His Flesh and Blood in the most Blessed Sacrament.
[3]Cornelius a Lapide in his Great Commentary writes, So we, by reason of our sinful lusts, were as wandering sheep, treading the path which led to perdition, without a thought of God or of heaven, or of the salvation of our souls.