Marriage

Marriage's fundamental motivation must be to glorify God.
So, whether you eat or drink, or whatever you do, do all to the glory of God. (1 Corinthians 10:31 ESV)

Love
We love, because He first loved us. (1 John 4:19 NASB)
If ye love me, keep my commandments. (John 14:15 KJV)

Companionship
Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh. (Genesis 2:24 KJV)
Two are better than one, because they have a good reward for their toil. For if they fall, one will lift up his fellow. But woe to him who is alone when he falls and has not another to lift him up! Again, if two lie together, they keep warm, but how can one keep warm alone? And though a man might prevail against one who is alone, two will withstand him - a threefold cord is not quickly broken. (Ecclesiastes 4:9-12 ESV)

Procreation
So God created man in his own image, in the image of God created he him; male and female created he them. And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth. (Genesis 1:27-28 KJV)

Sex
Marriage is to be held in honor among all, and the marriage bed is to be undefiled; for fornicators and adulterers God will judge. (Hebrews 13:4 NASB)

Conditions
1. There is One that you need to love more than your spouse
And thou shalt love the LORD thy God with all thine heart, and with all thy soul, and with all thy might. (Deuteronomy 6:5 KJV)

2. Your partner must also agree to rule number one
Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness? (2 Corinthians 6:14 KJV)

3. There is hierarchy in marriage
Wives, submit to your own husbands, as to the Lord. (Ephesians 5:22 ESV)

4. There is sacrifice in marriage
Husbands, love your wives, just as Christ also loved the church and gave Himself up for her, (Ephesians 5:25 NASB)

5. It is life long
And he answered and said unto them, Have ye not read, that he which made them at the beginning made them male and female, and said, For this cause shall a man leave father and mother, and shall cleave to his wife: and they twain shall be one flesh? Wherefore they are no more twain, but one flesh. What therefore God hath joined together, let not man put asunder. (Matthew 19:4-6 KJV)

6. There are those whom you cannot marry
None of you shall approach any one of his close relatives to uncover nakedness. I am the Lord. You shall not uncover the nakedness of your father, which is the nakedness of your mother; she is your mother, you shall not uncover her nakedness. You shall not uncover the nakedness of your father's wife; it is your father's nakedness. You shall not uncover the nakedness of your sister, your father's daughter or your mother's daughter, whether brought up in the family or in another home. You shall not uncover the nakedness of your son's daughter or of your daughter's daughter, for their nakedness is your own nakedness. You shall not uncover the nakedness of your father's wife's daughter, brought up in your father's family, since she is your sister. You shall not uncover the nakedness of your father's sister; she is your father's relative. You shall not uncover the nakedness of your mother's sister, for she is your mother's relative. You shall not uncover the nakedness of your father's brother, that is, you shall not approach his wife; she is your aunt. You shall not uncover the nakedness of your daughter-in-law; she is your son's wife, you shall not uncover her nakedness. You shall not uncover the nakedness of your brother's wife; it is your brother's nakedness. You shall not uncover the nakedness of a woman and of her daughter, and you shall not take her son's daughter or her daughter's daughter to uncover her nakedness; they are relatives; it is depravity. And you shall not take a woman as a rival wife to her sister, uncovering her nakedness while her sister is still alive. (Leviticus 18:6-18 ESV)
Thou shalt not commit adultery. (Exodus 20:14 KJV)
Thou shalt not lie with mankind, as with womankind: it is abomination. (Leviticus 18:22 KJV)
If a man also lie with mankind, as he lieth with a woman, both of them have committed an abomination: they shall surely be put to death; their blood shall be upon them. (Leviticus 20:13 KJV)
And you shall not lie with any animal and so make yourself unclean with it, neither shall any woman give herself to an animal to lie with it: it is perversion. (Leviticus 18:23 ESV)
Whoever lies with an animal shall be put to death. (Exodus 22:19 ESV)
"Cursed be anyone who lies with any kind of animal." And all the people shall say, "Amen." (Deuteronomy 27:21 ESV)
If a man lies with an animal, he shall surely be put to death, and you shall kill the animal. If a woman approaches any animal and lies with it, you shall kill the woman and the animal; they shall surely be put to death; their blood is upon them. (Leviticus 20:15-16 ESV)