What does Luke 15:24 mean?
The younger son of a landowner chose to live as if his father—and God—were dead (Luke 15:11–12), but it was really he who "died." He perfectly mirrored Paul's description in Ephesians 2:1–2:"And you were dead in the trespasses and sins in which you once walked, following the course of this world, following the prince of the power of the air, the spirit that is now at work in the sons of disobedience"The son took his inheritance and spent it on wild living (Luke 15:13) and prostitutes (Luke 15:30). He indulged in relationships that kill God's intent to create life in families and communities. When the money was gone, a famine came, and the son nearly died of starvation. He was spiritually dead because of his sin, relationally dead because the "friends" he chose did not care about his life, and nearly physically dead due to the famine.
Standing amidst another man's pigs, jealous of the pigs' food, the son took the first step toward life by realizing he was dead. Then he took the next step: accepted that he needed to repent for his squandered life. Finally, he returned to the father who gave him life (Luke 15:14–19). His father quickly returned him to life, physically and relationally. God the Father returned him to spiritual life. As the son's earthly father celebrated, so did his heavenly Father (Luke 15:20–23).
However, not everyone celebrates. The Pharisees and scribes refuse to acknowledge the restored spiritual lives of the sinners and tax collectors who swarm Jesus (Luke 15:1–2). In the same way, the prodigal son's older brother cannot accept that anyone who has sinned so egregiously should be restored by their father.