And Adam called his wife's name Eve; because she was the mother of all living. (Genesis 3:20, Holy Bible, KJV)
Nevertheless, to avoid fornication, let every man have his own wife, and let every woman have her own husband. (1 Corinthians 7:2, Holy Bible, KJV)
Nevertheless neither is the man without the woman, neither the woman without the man, in the Lord. (1 Corinthians 11:11, Holy Bible, KJV)
Behold, their husbands love their wives, and their wives love their husbands; and their husbands and their wives love their children. (Jacob 3:7, Book of Mormon)
Wherefore, my brethren, hear me, and hearken to the word of the Lord: For there shall not any man among you have save it be one wife. (Jacob 2:27, Book of Mormon)
And again, verily I say unto you, that whoso forbiddeth to marry is not ordained of God, for marriage is ordained of God unto man. (Doctrine and Covenants 49:15)
We, the First Presidency and the Council of the Twelve Apostles of The Church of Jesus Christ of Latter-day Saints, solemnly proclaim that marriage between a man and a woman is ordained of God and that the family is central to the Creator’s plan for the eternal destiny of His children...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. (The Family a Proclamation to the World)
Many in the world are confused about the concept of marriage. Some claim it to be no more than a civil institution - a concoction of man. Others claim it to be a flexible concept, amenable to change as society's views evolve. And still others are firm in their belief that marriage is a sacred union between one man and one woman - an institution appointed by God; a concept not subject to alteration.
Many appeal to the Bible as they make their claims. Some use scripture to support the current "definition" of marriage. Others use it to refute. No matter the stance, it is clear that the question will not be settled by an appeal to the Bible alone. The variance in interpretation of that body of scripture is too vast. Reference solely to the Bible on this point is as precarious and futile as is a door with only one hinge. Even the Bible itself is clear about it's utility in solidarity: "In the mouth of two or three witnesses shall every word be established" (Matthew 18:16).
The plain and precious doctrines contained in the Book of Mormon serve as a second hinge upon which the door of truth is hung.
Moreover, the clarity and precision of modern-day revelation and scripture leave no question as to the concept and definition of marriage.
Taken together, the Bible, the Book of Mormon, and modern-day revelation through prophets of God boldly and perfectly answer every question regarding marriage. God's definition of marriage is immutable, even as He is. It was the same in the days of Adam and Eve as it is in our day. Those who wish to redefine marriage according to a "new morality" do not understand, or simply refuse to believe, that marriage is a divine institution, ordained by God to form the foundation of eternal families.