When God makes a covenant with us, God says: "I will love you with an everlasting love. I will be faithful to you, even when you run away from me, reject me, or betray me." In our society we don't speak much about covenants; we speak about contracts. When we make a contract with a person, we say: "I will fulfill my part as long as you fulfill yours. When you don't live up to your promises, I no longer have to live up to mine." Contracts are often broken because the partners are unwilling or unable to be faithful to their terms.
But God didn't make a contract with us; God made a covenant with us, and God wants our relationships with one another to reflect that covenant. That's why marriage, friendship, life in community are all ways to give visibility to God's faithfulness in our lives together.
-Fr Henri Nouwen