"15 The LORD God took the man and put him in the garden of Eden to work it and keep it. 16 And the LORD God commanded the man, saying, “You may surely eat of every tree of the garden, 17 but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die.”
18 Then the LORD God said, “It is not good that the man should be alone; I will make him a helper fit for him.” 19 Now out of the ground the LORD God had formed every beast of the field and every bird of the heavens and brought them to the man to see what he would call them. And whatever the man called every living creature, that was its name. 20 The man gave names to all livestock and to the birds of the heavens and to every beast of the field. But for Adam there was not found a helper fit for him. 21 So the LORD God caused a deep sleep to fall upon the man, and while he slept took one of his ribs and closed up its place with flesh. 22 And the rib that the LORD God had taken from the man he made into a woman and brought her to the man. 23 Then the man said,
“This at last is bone of my bones
and flesh of my flesh;
she shall be called Woman,
because she was taken out of Man.”
24 Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh. 25 And the man and his wife were both naked and were not ashamed."
Here we have the first wedding in human history. God walks Adam and Eve down the aisle. He gives Adam a 'helper', who is like Adam but different. They share the same nature, being human, but are different persons.
Sinclair Ferguson comments:
Adam's "instinctive response to his first sight of Eve was to recognize that she was someone different from him (she was another person and a woman!). yet she was someone in whom he could see himself - in distinction from all the other life forms in creation she was 'fit for' or 'corresponding to' him (Genesis 2:18-20). In this sense Eve was the one companion fully suited to him, who would turn the 'not good' of his being alone into the 'very good' of a new, covenant relationship in which he would discover at a new depth what it meant to be the image of God, sharing now - as his Triune Creator had done from all eternity - in a world of intimate fellowship with another who shared his nature."1
"...[Adam] would discover at a new depth what it meant to be the image of God, sharing now...in a world of intimate fellowship with another who shared his nature."
Here's what Ferguson is saying: Marriage, a one-flesh relationship between a man and a woman, was intended to give us a taste of God's love, experienced as intimate fellowship. God is love (1 John 4:7-12). The Bible's teaching is that God is Father, Son and Holy Spirit. They are the same in substance, all God. They are of the same nature. But God is three persons. For all of eternity God has been in a loving intimate fellowship with another who is of the same nature. The Father loving the Son and the Son loving the Father and the Spirit binding them together in love.
Therefore, marriage is a gift from God designed to bring two different persons (a man and a woman) together who are similar (both image bearers of God) to be an image of God's self-less love. Marriage is a good thing, but not a god thing.
The apostle Paul tells us more in Ephesians 5:31-32. He quotes Genesis, "Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh," and then drops a bombshell:
Adam and Eve's marriage and intimacy refers to Christ and the Church!
God created marriage to show us how Jesus loves His people, the church. Eve was given to Adam to picture God giving Jesus the Church. Jesus looks at the church, His bride, with a married kind of love. Paul calls it a mystery, even as He tells us why Jesus died. Jesus' sacrificial love is ours in order to make His bride: holy and without blemish. He loved us so much that he became like us (flesh of my flesh) so that we might become like Him (righteous).
"For our sake [God] made him [Jesus] to be sin who knew no sin so that in him, we might become the righteousness of God"
2 Corinthians 5:21
Do you hear the similarities? Jesus, someone of another nature (God) became like us on the cross, so that we might become one (in Him), being like Him.
This takes the pressure off marriage because Your spouse is not Your reason for living. He or she cannot give you the affection that our hearts crave because we were made to find marital satisfaction in relationship to Jesus Christ. Which means we can be married or single and find a deep satisfaction in Christ's covenant love for the Church, His bride. This makes us unusual because we can say that it is not good for anyone to be alone. We are made to be in relationships. But we can also say that it is good to be single in Christ because Jesus died to make us His spouse. And it is good to be married in Christ because Jesus died to make us His spouse.
Do you know how to experience this kind of satisfaction in Christ?
For by grace you have been saved through faith. And this is not your own doing; it is the gift of God. ~Ephesians 2:8
1Sinclair Fergusion, Faithful God: An Exposition of the Book of Ruth, 90.