The Family: A Proclamation to the World states that “the family is
ordained of God. Marriage between man and woman is essential to His eternal
plan. Children are entitled to birth within the bonds of matrimony, and to be
reared by a father and a mother who honor marital vows with complete fidelity.”

Complete Fidelity; what does
this mean?
Fidelity is faithfulness and devotion. I believe fidelity in marriage is
not just about abstaining from sex outside marriage; it is so much more than
that. Kenneth W. Matheson who is a
Professor at the School of Social Work, at Brigham Young University has said
that “fidelity includes refraining from physical contact—but that is not all.
Fidelity also means complete commitment, trust, and respect between husband and
wife. Inappropriate interactions with another person can erode fidelity.”
Complete fidelity equals complete commitment, complete trust and complete
respect. It is not a partial thing; couples need to devote their time and
energy to their spouse and family.
We live in a time where the world looks upon chastity and fidelity as
an afterthought. Gordon B Hinckley had said that we must “stand above the
sleaze and the filth and the temptation which is all about you.” Satan wants us
to fail and he tries with all his power to tempt us. He is subtle and cunning. I
do not believe that a person wake up one day and decides that they are going to
be unfaithful. It is something that develops gradually and stems from thoughts
and feelings in the mind and in the heart.

How can you maintain fidelity in
marriage?
Spouses can make sure to spend time with each other and listen to each
other. Husband and wife can control their thoughts and avoid situations that
would cause them to waver. If put in a situation that could pose as a temptation; I suggest a person have a preset response. Just like Joseph knew that he was not going to give into the temptation of Potiphar's wife and fled, so can we in our lives know exactly what we will do in these cases. Marriage is sacred, it is not only a covenant made
between spouses but also before God. I know that fidelity in marriage is
essential to a successful marriage. Couples who are faithful in keeping their
covenants will have happiness and gain the rewards that are available from God.
References
Matheson, K.W. Fidelity in Marriage: It’s More Than You Think Barlow, B.A. They Twain Shall Be One: Thoughts on Intimacy in Marriage
The Family: A Proclamation to the World
Hinckley, G.B (1998) “Walking in the Light of the Lord” Ensign