334. Is it necessary to be celibate to receive the sacrament of Holy Orders?It is always necessary to be celibate for the episcopacy. For the priesthood in the Latin Church men who are practicing Catholics and celibate are chosen, men who intend to continue to live a celibate life “for the kingdom of heaven” (Matthew 19:12). In the Eastern Churches marriage is not permitted after one has been ordained. Married men can be ordained to the permanent diaconate.
Further reading: CCC 1579-1580; 1599335. What are the effects of the sacrament of Holy Orders?
This sacrament yields a special outpouring of the Holy Spirit which configures the recipient to Christ in his triple office as Priest, Prophet, and King, according to the respective degrees of the sacrament. Ordination confers an indelible spiritual character and therefore cannot be repeated or conferred for a limited time.
Further reading: CCC 1581-1589336. With what authority is the priestly ministry exercised?Ordained priests in the exercise of their sacred ministry speak and act not on their own authority, nor even by mandate or delegation of the community, but rather in the Person of Christ the Head and in the name of the Church. Therefore, the ministerial priesthood differs essentially and not just in degree from the priesthood common to all the faithful for whose service Christ instituted it.
Further reading: CCC 1547-1553; 1592