Vow of Celibacy: Why Priests Do Not Marry
Some quote I Timothy 4:1-3 to tell that celibacy is a doctrine of demons.
Timothy 4:1-3"The Spirit clearly says that in later times some will abandon the faith and follow deceiving spirits and things taught by demons. Such teachings come through hypocritical liars, whose consciences have been seared as with a hot iron. They forbid people to marry and order them to abstain from certain foods, which God created to be received with thanksgiving by those who believe and who know the truth."
Celibacy in the Catholic Church is a discipline, not a doctrine.
1 Corinthians 7:6-8"I say this as a concession, not as a command. I wish that all of you were as I am. But each of you has your own gift from God; one has this gift, another has that.Now to the unmarried and the widows I say: It is good for them to stay unmarried, as I do."
Priests and nuns were not restricted from marriage, they vow not to marry. This is what we call Vow of Celibacy.
Matthew 19:12"Some are incapable of marriage because they were born so; some, because they were made so by others; some, because they have renounced marriage for the sake of the kingdom of heaven. Whoever can accept this ought to accept it.”
Apostle Paul suggested celibacy so that the attention won't be divided but rather focused only for God.
1 Corinthians 7:32-35 "I would like you to be free from concern. An unmarried man is concerned about the Lord’s affairs—how he can please the Lord. But a married man is concerned about the affairs of this world—how he can please his wife— and his interests are divided. An unmarried woman or virgin is concerned about the Lord’s affairs: Her aim is to be devoted to the Lord in both body and spirit. But a married woman is concerned about the affairs of this world—how she can please her husband. I am saying this for your own good, not to restrict you, but that you may live in a right way in undivided devotion to the Lord."