St. Peter Damian

"Just as Saint Basil establishes that those who incur sins (against nature) … should be subjected not only to a hard penance but a public one, and Pope Siricius prohibits penitents from entering clerical orders, one can clearly deduce that he who corrupts himself with a man through the ignominious squalor of a filthy union does not deserve to exercise ecclesiastical functions, since those who were formerly given to vices…become unfit to administer the Sacraments."

Saint Peter Damian’s Liber Gomorrhianus (Book of Gomorrha)1051