Two strangers find it much easier to agree that they disagree.
Two kinsmen find it almost impossible, because the very possibility of distancing oneself from others, from their laws and customs and the clannish unity of the family, is something the family cannot accept.
Quarrels can continue endlessly but separation cannot be countenanced.
Even when the situation becomes intolerable in practical terms, and the resentment and dislike reach a point at which it is necessary to effect a physical parting between the antagonists, there persists nevertheless a feeling of responsibility for the other.
In spite of what I think, the other remains my kinsman, my brother.
And whatever he does is somehow, after all, connected with me.
–Rabbi Adin Steinsaltz