I want to know if it’s good for two married persons to live their whole life without having sexual relations and not to have children?
No. Not at all. And here’s why.
The marriage of the two is the union to form a single body
This is God’s definition of marriage, whose author is also He.
For this reason a man shall leave his father and his mother, and be joined to his wife; and they shall become one flesh. (Genesis 2:24)(NASB)
To be joined to your wife means the sexual relationship and that is seen better in the following passage written by the apostle Paul:
Or do you not know that the one who joins himself to a prostitute is one body with her? For He says, “THE TWO SHALL BECOME ONE FLESH.” But the one who joins himself to the Lord is one spirit with Him. Flee immorality. Every other sin that a man commits is outside the body, but the immoral man sins against his own body. (1 Corinthians 6:16-18)(NASB)
As you see, it is used the same phrase “to be joined” that is used with reference to the sexual act.
Sexual relationship between spouses is clean
For this sexual relationship was created, to be an expression of love of the two in marriage. Any other sexual relationship before marriage or outside marriage taints the intimate life of married couples, as it is written in the Epistle to Hebrews:
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)
It is a duty of the spouse
The apostle Paul wrote:
The husband must fulfill his duty to his wife, and likewise also the wife to her husband. The wife does not have authority over her own body, but the husband does; and likewise also the husband does not have authority over his own body, but the wife does. Stop depriving one another, except by agreement for a time, so that you may devote yourselves to prayer, and come together again so that Satan will not tempt you because of your lack of self-control. But this I say by way of concession, not of command. (1 Corinthians 7:3-6)(NASB)
If you do not want to have sexual relations, or if you are not ready to assume your responsibility as you have as a husband or wife towards your future marriage partner, you should not marry in any case.
Translated by Felicia Rotaru