God has already given us clear instructions and godly examples regarding family relationships in the Bible. "Children, obey your parents in the Lord, for this is right" (Eph. 6:1). "Honor your father and mother" (Exodus 20:12). "Behold, how good and pleasant it is when brothers dwell in unity" (Ps. 133:1). "You shall not hate your brother in your heart" (Lev. 19:17).
More than that, we know how we are to treat our family because it has been written on our hearts, "They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them" (Rom. 2:15). And when we are in such a state of mind and heart as to ignore those basic morals, I highly doubt we would change our tune just because we read a story of Jesus sharing his toys (though I would be interested in seeing just how that scene played out). The majority of references to "brother" in the Bible have more to do with a common ancestry or common heart than with common parents. Among the Israelites all other Israelites (and Edomites, as they come from Esau, Israel's brother) were considered brothers. Jesus said, "whoever does the will of my Father in heaven is my brother and sister and mother" (Matt. 12:50). The deeper I go, the more I am convinced that how siblings are to treat each other is a given, because that is the example used for how we are to treat everyone else. "Treat younger men like brothers...younger women like sisters, in all purity" (1 Tim. 5:1,2).
Jesus does have a few things to say about brothers. Though he is likely referring to the brotherhood of spirit rather than that of blood.
But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, "You fool!" will be liable to the hell of fire. So if you are offering your gift at the altar and there remember that your brother has something against you, leave your gift there before the altar and go. First be reconciled to your brother, and then come and offer your gift. (Matt. 5:22-24)Jesus also says that we are not only to reconcile ourselves to our brothers for our own actions, but also to forgive the actions of our brothers not just a few times, but always (Matt. 18:21-22). Brothers are to hold each other accountable for their actions, not out of judgment (for we each have a plank in our own eye, Matt. 7:1-5), but out of a desire to restore the brother back into right relationship with God and others (Matt. 18:15-17).
Are there a lot of negative examples of sibling interaction in the Bible? Wow, Bessie, are there ever. The first kid ever born kills his brother. Jacob steals Esau's birthright and blessing. Jacob's sons sell Joseph into slavery (in lieu of killing him). King David's kids are messed up! Jesus' own brothers try to draw Jesus out to where the authorities can take him down. But these are just sinful flesh and blood human beings like any one of us. It isn't that they didn't know how they aught to treat each other. They did it because they desired something else; something selfish. "Each one is tempted when he is lured and enticed by his own desire" (James 1:14).
It strikes me that Jesus did not come to live out every possible example of showing love toward others. Jesus was never married (on earth). He never had kids. We don't get to see how Jesus interacted with his employer. Instead of demonstrating every possible action and reaction of love he demonstrated the direction of love and the extent to which love will go. His example makes love more applicable to every situation in life than it would have been if he had spent his time specifying how to respond in every situation. Love isn't about the specific response. Love is about the heart. Not what we feel like doing, but looking at people the way God looks at them and caring about their best interests. That is what Jesus demonstrated. That is how he lived. And I am sure that he lived the same way toward his family while he was growing up as he did toward his disciples and the crowds.
