Clement of Alexandria (~150-220 AD) "Stromata" Book VII, Chapter XI
Canons XXVII and XXXIII of the Council of Elvira 295-302 AD
Council of Nicea 325 AD
Pope Siricius "Dicreta" 385 AD
Pope Siricius "Cum in unum" 386 AD
Synod of Rome 386 AD
Second Council of Carthage 390 AD
Codex canonum Ecclesiae Africanae 419 AD
catechesis of St. Cyril of Jerusalem (313-386 AD)
"Letter to Pammachius" St. Jerome (347-419 AD)
St. Jeromes' polemic with Vigilantius from Gaul 406 AD
"De conjugiis adulterinis" St. Augustine 419 AD
"Breviatio Ferrandi" ~550 AD
Third Council of Toledo 589 AD
councils held under St. Caesarius of Arles sixth century AD
Irish Penitentials sixth century AD
Poenitentiale Vinniani, no. 27, sixth century AD
Council of Metz 888 AD
Council of Mainz 888 AD
Council of Rheims 909 AD
Synod of Rome 1077 AD
First Lateran Council Canons III, XI 1123 AD
Second Lateran Council Canons VI, VII, XI 1139 AD
The logistical difficulties in disseminating and enforcing the discipline does not mitigate the fact that it existed and was practiced long before the 12th century and has it's origins in the Church with the Apostles.