He served as bishop of Urgell (783–99) and advocated the christology known as Spanish Adoptionism because it originated in the lands of the former Visigothic Kingdom in Spain.
[1] Felix became bishop at an unknown date and lived at the monastery of Sant Sadurní de Tavèrnoles, in the foothills of the Pyrenees.
This separated the bishopric of Urgell politically from the bulk of the Spanish (Visigothic) church, which was still under Islamic rule.
[1] About this time Felix came to prominence for his christological teachings, which attracted criticism from the Anglo-Saxon scholar Alcuin of York.
In 792, the Frankish king Charlemagne convened a council at Regensburg for the purpose of condemning Felix for heresy.