As a Catholic, I believe and fully accept the teaching of the Church is God's rule according to the loosing and binding stated in Matthew 16:18 and many other passages.
New Advent states:
Celibacy is the renunciation of marriage implicitly or explicitly made, for the more perfect observance of chastity, by all those who receive the Sacrament of Orders in any of the higher grades. The character of this renunciation, as we shall see, is differently understood in the Eastern and in the Western Church. Speaking, for the moment, only of Western Christendom, the candidates for orders are solemnly warned by the bishop at the beginning of the ceremony regarding the gravity of the obligation which they are incurring. He tells them:
You ought anxiously to consider again and again what sort of a burden this is which you are taking upon you of your own accord. Up to this you are free. You may still, if you choose, turn to the aims and desires of the world (licet vobis pro artitrio ad caecularia vota transire). But if you receive this order (of the subdiaconate) it will no longer be lawful to turn back from your purpose. You will be required to continue in the service of God, and with His assistance to observe chastity and to be bound for ever in the ministrations of the Altar, to serve who is to reign.
By stepping forward despite this warning, when invited to do so, and by co-operating in the rest of the ordination service, the candidate is understood to bind himself equivalently by a vow of chastity. He is henceforth unable to contract a valid marriage, and any serious transgression in the matter of this vow is not only a grievous sin in itself but incurs the additional guilt of sacrilege.
It is a dicsipline highly praised and lived by Christ, the Apostles and St. Paul, for starters.