The Donatists were an early heterodox Christian sect whose primary heretical view referred itself to the nature of the sacraments:
The Donatists refused to accept the sacraments and spiritual authority of the priests and bishops who had fallen away from the faith during the persecution. Many church leaders had gone so far as to turn Christians over to Roman authorities and had handed over sacred religious texts to authorities to be publicly burned. These people were called traditors (“people who had handed over”). These traditors had returned to positions of authority under Constantine I, and the Donatists proclaimed that any sacraments celebrated by these priests and bishops were invalid.
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The second question was the validity of sacraments confected by priests and bishops who had been apostates under the persecution. The Donatists held that all such sacraments were invalid: by their sinful act, such clerics had rendered themselves incapable of celebrating valid sacraments. This is known as: ex opere operantis — Latin for from the work of the one doing the working, that is, that the validity of the sacrament depends upon the worthiness and holiness of the minister confecting it.
The prevailing orthodoxy, then as now, was that the validity of the sacraments was ex opere operato – that is to say, the sinfulness, guilt, or otherwise questionable behaviour of the officiant had no relation to the effectiveness of the sacrament. Instead, the grace conferred proceeded entirely from the intention of the officiant and penitent, as well as, of course, from God, whose instrument the officiant was.
Ex opere operato – if it’s good enough for the Christians, it’s probably good enough for the cops.
