The concept of celibacy is used in our language to designate that state that a person voluntarily adopts and that implies remaining single for the rest of their life or a large part of it, that is, as long as their existence lasts they will not marry, You will not have a stable or short-lived partner, and you will not have sex with anyone. Because in celibacy, singleness and non-practice of sex go hand in hand, that is, one could never speak of celibacy if the person has sexual relations with someone, it would in no way be authentic celibacy.
Although celibacy is a state that is mostly linked to the Catholic religion, because precisely the priests who promulgate this faith are obliged by the law that governs their doctrine to remain celibate for the rest of their lives and this obviously influenced the fact that the concept is mainly associated with religion, it is also common to use the term when it is intended to express that an individual has chosen such a state but mobilized by a personal decision in which the religious question did not intervene in any way.
Meanwhile, in the precise case of Catholic priests, celibacy is a condition without equanom when it comes to being ordained as such. They could never do it if they are married or if they have a loving relationship with a woman. And of course once they become priests and while they are, they will no longer be able to intimate with anyone. Such a fact is punishable.
This same situation is transferred to the nuns, that is, the nuns also assume a commitment of celibacy once they become such.
However, it is important to note that there are other religious beliefs that do not oblige their official representatives to remain celibate, but on the contrary, they allow them to maintain a common and ordinary life at the same time as that of any individual who does not maintain a formal relationship with a church, that is: getting married, having sex, having children, among others.
For example, in some religions, those who play the equivalent role of a priest, such as the rabbis in Judaism, are allowed to marry, start a family and all of this is integrated into religious life.