Newman changes his mind

While I am now as clear in my acceptance of the principle of dogma, as I was in 1833 and 1816, so again I am now as firm in my belief of a visible Church, of the authority of Bishops, of the grace of the sacraments, of the religious worth of works of penance, as I was in 1833. I have added Articles to my Creed; but the old ones, which I then held with a divine faith, remain.

3. But now, as to the third point on which I stood in 1833, and which I have utterly renounced and trampled upon since,—my then view of the Church of Rome;—I will speak about it as exactly as I can. When I was young, as I have said already, and after I was grown up, I thought the Pope to be Antichrist. […]  From my boyhood and in 1824 I considered, after Protestant authorities, that St. Gregory I. about A.D. 600 was the first Pope that was Antichrist, though, in spite of this, he was also a great and holy man; but in 1832-3 I thought the Church of Rome was bound up with the cause of Antichrist by the Council of Trent.

(source: Newman Reader – Apologia (1865) – Chapter 2)