I am having trouble finding out how clerical celibacy came about in the Bishopric and higher.
Some told me the Council of Nicea of which St. Paphnute recommended it, and then canonized it. However, other sources say the exact opposite, that St. Paphnute, a celibate man himself, was against enforcing celibacy. In addition, there are no canon (not even the EO later ones) that enforce celibacy as a PREREQUISITE to the Bishopry.
The closest thing I got on the EO side was the Council in Trullo that had a canon that stated that a married priest, if elevated to the Bishopric, should be seperated from his wife, and his wife would go to a convent, or something like that.
How about us OO's? Since when were all bishops supposed to be celibate?