What does Matthew 19:12 mean?
After hearing Jesus' declaration that divorce is unlawful except in the case of sexual immorality, the disciples have responded that it is better not to marry, at all. By this, they seem to mean that marriage is not worth the risk if divorce is not an option. Jesus does not insist everyone must get married. Instead, Jesus connects marriage to sexual appetite, saying that not everyone is able to "receive this" idea of not getting married (Matthew 19:8–11). Now Jesus begins to talk about different kinds of eunuchs.The word eunuch generally refers to a man who has been castrated, meaning that his sexual organs have been surgically removed and/or disabled. In some ancient Eastern courts, male servants who tended royal women were castrated in order to avoid the possibility of sexual activity. Advisors and others close to kings were also made eunuchs, so they would not be corrupted by sex or distracted by a family. These are the most literal kind of eunuchs, those "made…by men."
Jesus expands on the concept of a eunuch here, describing some men as being born eunuchs, meaning those who naturally lack sexual desire or the ability to have sex. This would seem to include those who are born with physical complications, as well as those with sexual desires incompatible with marriage.
Then Jesus adds a third kind of eunuch, those who have made themselves so for the sake of the kingdom of heaven. Given the broader sense in which Jesus is using the word, He does not mean literal castration. Rather, He is speaking figuratively of those who have set aside their sexual desire and right to be married in order to serve the Lord with a more single-minded devotion. He concludes by saying that the person who can receive this condition should do so.
Paul says something very similar in 1 Corinthians 7. He describes his ability to be unmarried and unburdened by overwhelming sexual desire as a gift from God that allows him to be undistracted in his ministry. He makes it clear, though, that not everyone has this gift and that they should marry instead of "burning with passion" and risking sexual sin (1 Corinthians 7:7–9).