What does Luke 12:13 mean?

Jesus is trying to teach His disciples how they should live with the kingdom of God in mind. The setting, however, is not conducive to private conversation. They are surrounded by a mob of thousands of people, all of whom are trying to get to Jesus (Luke 12:1). A man interrupts to demand Jesus settle a conflict with his brother.

We don't know the background of the request. Culturally, it would be normal for a father to leave most of his possessions to his eldest son, but he may also leave the estate to all his sons as a group. It's possible their father has left all or the bulk of his estate to the brother. We don't know if this man inherited nothing, or less than he felt he was owed, or if he wants to break up the estate and strike out on his own. We just know he is unsatisfied.

The interruption provides interesting contrasts to much of the rest of the unit (Luke 12:1—13:9):

<&bull> This man is concerned about money, while Jesus has just told His disciples they will face persecution and death (Luke 12:1–12).
<&bull> This man demands riches, while Jesus wants His disciples to rely on God's provision for the bare minimum they will need to survive (Luke 12:22–34).
<&bull> This man is concerned about what he thinks he deserves, while Jesus wants His disciples to take responsibility for the care of other Christ-followers (Luke 12:35–48).
<&bull> This man is fighting with a brother, while the disciples will have to separate from family because of their devotion to Jesus (Luke 12:49–53).
<&bull> This man is causing conflict when he should consider how the kingdom of God is coming near and settle with everyone with whom he bickers (Luke 12:57–59).
<&bull> Finally, this man is focusing on worldly treasure when he should be thinking about his limited time to repent and reconcile with God (Luke 13:1–9).

Jesus answers with the parable of the rich fool who decides to tear down his barns and build bigger ones to hold his great harvest. That night, however, he dies; his wealth is worth nothing. Like the rich fool, the brother "lays up treasure for himself and is not rich toward God" (Luke 12:21).

The man refers to Jesus as "teacher." Jews often went to respected leaders and teachers to settle disputes, so calling on Jesus isn't unprecedented. If the matter were more serious, the man would take the issue to a formal judge, the synagogue, or the elders at his city's gates. The man is not looking for a fair ruling, however. He just wants Jesus to take his side and force his brother to work the issue out in his preferred way.