Novatian of Rome is noteworthy for two reasons. In the first place he was the “antipope” of the “Puritan” party in the church. Secondly, he gave to the Western Church the first full-length treatment of the Trinity. Perhaps disappointed by the elevation of Cornelius* as pope (251), Novatian joined those who demanded that the Christians who had apostatized during the Decian persecutions (249-50) should not be welcomed back into the fellowship of the church. Novatian's group formed themselves into their own party, under strict discipline. This separatist movement continued for many centuries. Their orthodoxy was never in doubt: Acacius,* one of their leading bishops during the Arian controversy, strongly repudiated Arianism. The, which set out terms for the reception of the Novatians back into the church, demanded no change of doctrine. Novatian's work on the Trinity was strongly Trinitarian in character and maintained the full deity of Christ, though inclining to a form of the “kenotic” theory. Men such as Cornelius were not unnaturally critical of Novatian, who was nonetheless a vigorous champion of true Christology. Novatian died as a martyr during the persecutions under Valerian.