What is a young Christian man to do when he is around 20 years old and doesn’t know about getting married? Maybe he doesn’t really want to pursue marriage. Maybe he’s happy not being married. Or what about a young Christian woman in a similar position with similar thoughts? Must Christians get married? To be sure, there’s no direct command in Scripture for God’s people: “Thou Shalt Get Married.” However, in Scripture the normal life pattern for God’s people is marriage and, if the Lord wills, raising children. Even before the fall into sin God instituted marriage and told the man and woman to be fruitful and multiply. The command was repeated in the post-fall Noahic covenant God made with Noah and all creation (Gen. 9:7).
One other thing to think about is that in Scripture there is a sort of calling to celibacy (virginity) and singleness (1 Cor. 7:7-9; cf. Jesus’ words in Mt. 19:10-12). Singleness is certainly a biblical life option for Christians if the Lord so gifts and calls. However, if a Christian has strong and/or frequent desires for sexual intimacy, those desires are an indication that he or she should very much consider marriage (1 Cor. 7:1-2). If a Christian does not want to get married, it means he or she is committing himself or herself to celibacy (virginity) and sexual purity. Or in other words, if a Christian does not want to get married but does have a problem with pornography or sexual lust, that person most likely should get married: “It is better to marry than to burn with [sexual] passion” (1 Cor. 7:9b).
Calvin explains this topic well in the second book of his Institutes (II. viii. 42-43). These paragraphs are worth reading for sure – I’m glad a friend of mine recently pointed them out to me! I’ll put parts of Calvin’s discussion here (I’ve edited it slightly for readability).
Now, through the condition of our nature (created as man and woman), and by the lust aroused after the Fall, we – except for those whom God has released through special grace – are doubly subject to women’s society. Let each man, then, see what has been given to him. Virginity, I agree, is a virtue not to be despised. However, it is denied to some and granted to others only for a time. Hence, those who are troubled with incontinence (lack of sexual restraint) and cannot prevail in the struggle should turn to matrimony to help them preserve chastity (purity) in the degree of their calling. For those who do not receive this precept (virginity) [cf. Matt. 19:11], if they do not have recourse to the remedy offered and conceded them for their intemperance (the remedy is matrimony), are striving against God and resisting his ordinance. Let no one cry out against me—as many do today—that ‘with God’s help he can do all things.’ For God helps only those who walk in his ways, that is, in his calling [cf. Ps. 91:1, 14]. All who, neglecting God’s help, strive foolishly and rashly to overcome and surmount their necessities, depart from their calling. The Lord affirms that continence (sexual self-restraint) is a special gift of God, one of a kind that is bestowed not indiscriminately, not upon the body of the church as a whole, but upon a few of its members….
…We are informed by an open declaration, that it is not given to every man to keep chastity (pure) in celibacy (abstaining from sex), even if he aspires to it with great zeal and effort, and that it is a special grace which the Lord bestows only upon certain men, in order to hold them more ready for his work. Do we not, then, contend against God and the nature ordained by him, if we do not accommodate our mode of life to the measure of our ability? Here the Lord forbids fornication. He therefore requires purity and modesty of us. There is but one way to preserve it: that each man measure himself by his own standard.
Let no man rashly despise marriage as something unprofitable or superfluous to him; let no man long for celibacy unless he can live without a wife. Also, let him not provide in this state for the repose and convenience of the flesh, but only that, freed of this marriage bond, he may be more prompt and ready for all the duties of piety. And since this blessing is conferred on many persons only for a time, let every man abstain from marriage only so long as he is fit to observe celibacy (abstaining from sex). If his power to tame lust fails him, let him recognize that the Lord has now imposed the necessity of marriage upon him. The apostle proves this when he enjoins that to flee fornication “each man should have his own wife, and each woman her own husband” [1 Cor. 7:2]. Again: “If they cannot exercise self-control, they should marry” in the Lord [1 Cor. 7:9]. First, he means that the greater part of men are subject to the vice of incontinence (lack of sexual restraint); secondly, of those who are so subject he enjoins all without exception to take refuge in that sole remedy with which to resist unchastity (that is, marriage). Therefore if those who are incontinent (lack sexual restraint) neglect to cure their infirmity by this means (of marriage), they sin even in not obeying this command of the apostle. And let him who does not touch a woman not flatter himself, as if he could not be accused of immodesty, while in the meantime his heart inwardly burns with lust. For Paul defines modesty as “purity of heart joined with chastity of body.”…
John Calvin, Institutes, II.viii, 43.