Matthew 19:12 seems to suggest spiritual benefit from being a eunuch such that some might be led to make themselves eunuchs (castrate themselves) for the sake of the kingdom:
BLB Matthew 19: 10His disciples say to Him, “If this is the case of the man with the wife, it is better not to marry.” 11And He said to them, “Not all receive this word, but only those to whom it has been given. 12For there are eunuchs who were born thus from their mother’s womb, and there are eunuchs who were made eunuchs by men, and there are eunuchs who made themselves eunuchs for the sake of the kingdom of the heavens. The one being able to receive it, let him receive it.”
Likewise Wisdom of Solomon 3:14 seems to suggest that a godly eunuch is eligible for "the special gift of faith" and "an inheritance in the temple of the Lord" toward which the mind of a eunuch is more conducive, presumably because of an undivided devotion:
Wisdom of Solomon 3:14 And blessed is the eunuch, which with his hands hath wrought no iniquity, nor imagined wicked things against God: for unto him shall be given the special gift of faith, and an inheritance in the temple of the Lord more acceptable to his mind.
This could be a notion that is connected in the mind with the fact that castrated bulls become more docile and have less desire to breed.
Paul seems to view marriage as a distraction from devotion and service for the kingdom:
BLB 1 Corinthians 7: 6Now I say this by way of concession, not by way of command. 7And I wish all men to be even like myself. But each has his own gift from God; for one has this, but one that. 8Now I say to the unmarried and to the widows, it is good for them if they should remain as even I. 9But if they do not have self-control, let them marry; for it is better to marry than to burn with passion. ... 32And I desire you to be without concern. The unmarried man cares for the things of the Lord, how he should please the Lord; 33but the one having been married cares for the things of the world, how he should please the wife, 34and is divided. And the unmarried woman and virgin cares for the things of the Lord, that she should be holy both in body and in spirit; but the one having been married cares for the things of the world, how she should please the husband. 35Now I say this for your own benefit, not that I might place upon you a restraint, but for what is seemly and devoted to the Lord, without distraction.
Paul can be seen as enlarging on Jesus' teaching. Is Jesus' teaching about eunuchs for the kingdom applying the passage from Wisdom of Solomon?
It appears that the single life is also being recommended in the account of the widow of Asher:
NIV Luke 2: 36There was also a prophet, Anna, the daughter of Penuel, of the tribe of Asher. She was very old; she had lived with her husband seven years after her marriage, 37and then was a widow until she was eighty-four. She never left the temple but worshiped night and day, fasting and praying.
New International Version Psalm 27:4 One thing I ask from the LORD, this only do I seek: that I may dwell in the house of the LORD all the days of my life, to gaze on the beauty of the LORD and to seek him in his temple.
Psalm 65:4 Blessed are those you choose and bring near to live in your courts! We are filled with the good things of your house, of your holy temple.