The question is often asked of friends and acquaintances, 'Why do you have to marry in the Mormon Temple?' Maybe the question should be, 'Why wouldn't you want to marry in the Temple?'
The main reason is that it is ordained of God! Ordained meaning: decreed, established, especially appointed, which indicates that marriage is a divine institution.
Three scriptures in the Bible read as follows, I Corinthians 11:11 "Neither is the man without the woman, neither the woman without the man in the Lord." And, Genesis 2:18, "And the Lord God said, it is not good that the man should be alone; I will make him an help meet for him." And finally in Genesis 2:24, "Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh."1
Another question that might be asked is, 'Why was marriage ordained of God?' Some possible answers might be, to bring children into the world, to provide experience and to provide companionship.
In the Mormon temple, a man and woman are sealed together forever, but upon the condition that both are faithful to one another and obedient to the promises they have made to each other and to God. God is the foundation of the marriage!
Another reason to be married in the temple is that it tells a lot about the person you are about to marry and spend the rest of your life and all of eternity with. You both believe in the same things and you both have the same spiritual goals. You know that the person you are marrying has been and is obedient to the commandments of God and is worthy to enter the temple. You know that they are willing to make commitments to God, to you and to themselves. And lastly, it helps you to re-evaluate yourself and your commitment to your spouse and to God.
Does a temple marriage guarantee that a couple will live happily ever after? Of course not; disagreements, arguments and trials come to everyone, even those married in the Mormon temple. Being sealed in the temple is a great start to any Mormon marriage, but it only works as long as both spouses are totally obedient to the covenants they have made in the temple.
All couples go through the same issues once they are married. You are bringing two different people together who have come from two different backgrounds. Each has his own way of doing things, each has come from families with their own traditions and ways. So understandably there are going to be adjustments and disagreements. Discuss them, compromise and in some cases, agree to disagree. Through all of this adjustment there are three things to remember; each partner has made a commitment to God, they each made a commitment to each other, and each knows that the other partner will keep the commitments.
As each spouse lives the covenants and promises they have made, the little problems that arise are not serious and tend to disappear. One thing that is certain though: whenever there is a problem between a husband and wife in the relationship and is serious enough to threaten that relationship, you can be certain that one or the other, or both, is not living the commandments of God. Which means that one or both of the partners is not keeping the covenants, commitments or promises they made in the temple.2
When each are doing what God would have them do, that of keeping the commandments and serving each other and making God the center of their relationship, then when problems arise, they are handled with patience and unselfishness.
1 "Holy Bible; King James Version
2 "Marriage in the Lord's Way", part two, LDS Ensign magazine, 1998, by Elder Cree-L Kofford