What does Luke 12:45 mean?
When the master of a house goes away, good servants will keep lights on and stay prepared for his return, no matter how late he arrives. This illustration teaches how Jesus' followers should remain diligent in their responsibilities while they await His return and the fulfillment of the kingdom of God (Luke 12:35–40). Jesus wants His followers to understand that they will not know when He will return, so they need to remain watchful. Peter, however, seems to hear that Jesus is comparing the disciples to servants. In Peter's mind, there surely must be some differentiation between the Twelve and the "ordinary" people crowding around them (Luke 12:1, 41).Jesus allows that within servanthood some will be leaders, but leaders carry even more responsibility: they must make sure the believers in their care are fed properly. Sometimes, this is literal, like in the early church (Acts 6:1–6). Most of the time, this refers to providing the "bread of life": the truth about Jesus (John 6:35).
Now, Jesus describes a bad church leader. They grow tired of waiting for their master to return. They begin to think they are the master, and therefore entitled to the choice things in the house. They eat the master's food, drink his wine, and beat his servants. They don't realize the master will return unexpectedly. Because these "leaders" know what they are supposed to do and refuse to do it, they will be punished harshly (Luke 12:46–47).
Jesus' description is strikingly similar to God's description of the Jewish religious leaders in Ezekiel 34. These "shepherds" feed themselves instead of their "sheep," take what they want, refuse to heal the wounded, and abandon the lost. As a result, the sheep scatter, easy prey for wolves and lions (Ezekiel 34:1–6). God promises to rescue the sheep and "set up over them one shepherd, [his] servant David, and he shall feed them" (Ezekiel 34:23). This "David" is Jesus. The disciples are the fellow workers Jesus delegates to feed His sheep (1 Corinthians 3:9; John 21:15–17).