and accepted an official creed, adopting the language proposed by Athanasius. Modified by later councils, this became the Nicene Creed that Catholics recite at Mass on Sundays. The council anathematized anyone who said there was a time when the Son of God did not exist or that he was in any way different in substance from the Father. The bishops at the council thought they had won the battle when they condemned Arianism. They soon learned, though, that they hadn’t succeeded in quashing this heresy.