Ecclesiastes 4:9-12
Strong friendships all have a common ground on which they are sustained: they are there for each other. If a person suffers a setback a good friend will help them get back on their feet. If a person is in need of comfort a good friend will comfort them. And if a person finds themselves in the middle of conflict a good friend will help them to fight the battle. 
Building strong friendships require time, effort and vulnerability. But they are worth the price. Because friendships take so much of us, we need to make sure that Jesus is at the core of these friendships. When he is, our friendships won’t fray and our results will be blessed.