The following is a conversation between a married couple of 40 years: 

She says:

We have had good times and we have had bad times. But that's life, you know...I think the best thing in life about two people is when they're able to come back and say, "I'm sorry," or "I did see it wrong." He has been a real human being for me...as we grew, we grew stronger. I knew that he was good...you can feel that people love you. I just love my husband and he loves me. There's been times in our lives when I could say: "I don't think this is what I want out of life." But we always sit down and we talk about it and we give it another go...as you grow, and you're with someone for so long, you learn to get all that nurturing from them. He's my world. That's what he means to me. You know, the world our there is the world, but he is my world.

He says:

Sometimes I'll be laying in bed at night and I'll just be running this through my mind. And I think that God must have wanted us to be together. With all the turmoil...we're still together today, and we love one another and care about one another more now than we did when we first started...We have become like one. She means my whole life to me right now...when one of us has to go, pass away, I hope that it would be me. I want to go first...that is how much I love her. 

The commitment between this couple has grown from something wholly original. From the day they were married they both recognized that regardless of what the world threw their way, they were determined to stay together and in so doing they learned how to be each other's world. The commitment in a marriage begins with and is bound by covenant. 

Genesis 17:7-8 

"I will establish my covenant as an everlasting covenant between me and you and your descendants after you for the generations to come, to be your God and the God of your descendants after you. The whole land of Canaan, where you are now an alien, I will give as an everlasting possession to you and to your descendants after you; and I will be their God."

This character of God goes beyond any human conception into the realm of the heavenly bond between Christ and us, His children. Stanley Hauerwas comments on the community created in the covenant:

It is fidelity that comes by being formed by a community whose life is sustained by a God who has proved faithful to us through the call of he people, Israel, and the establishment of the new age in Jesus Christ. Only people so formed are capable of the kind of promise we make in marriage, that of life long fidelity.

God has set the example. He bound up His love for us through the very same bond that binds a marriage. Marriage then "in covenantal terms is seen as a sign reflecting the image of God and as a testimony of God's covenant with humanity."  The act of God towards His people and that of a marriage flows in and out of one another. We must be able to pursue the fidelity that goes beyond the commitment begun at a wedding. Jim Furrow, Ph.D. remarks "weddings are not marriage. Weddings are where people make promises. Marriages are where they then live out those promises."  The beauty of marriage lies in our ability to press in during hard times and see how the promises established in the covenant of marriage are what bring about the true growth towards Christ.