What exactly is intimacy?
It is the mutually physical, emotional, spiritual, and sexual union God designed exclusively between one man and one woman within marriage resulting from publicly professed, enduring commitment; selfless love, genuine trust, respect, and patience. These are the attributes that honor God and stand in stark contrast to everything the world believes and aggressively flaunts.
"Sexual intimacy reaches its maximum enjoyment when inside a marriage covenant—when two people make a lifetime committment to one another." — Pastor Dave Engbrecht
And as beautiful and important as the physical act is, intimacy encompasses so much more—namely, the depth and strength of the relationship itself—with Christ at the center:
Genesis 2:18 (NASB): "Then the Lord God said, "It is not good for the man to be alone; I will make him a helper suitable for him.""
Genesis 2:24 (NASB): "For this reason a man shall leave his father and his mother, and be joined to his wife; and they shall become one flesh."
It is uncommon because few believe God, nor are they willing to invest the time and effort for the results. Regardless, it does exist, and carries tremendous benefits.
Proverbs 18:22 (NASB): "He who finds a wife finds a good thing and obtains favor from the Lord."