Although a controversial view, there are some scholars who believe that many Christians in the Second Century Church believed a doctrine called Modalistic Monarchianism, which denies a trinity of persons but teaches the One God manifested himself in three different roles. One of the proponents of this view, Sabellius specifically taught that the One God was Father in Creation; the Son in Redemption; and the Spirit in Sanctification and Regeneration. I read a book many years ago, which asserted that Pope Zephyrinus (d. 217) also believed this although I do not know where they got their information. Supposedly, his successor, Pope Calixtus I also believed it but did not want to rock the boat with the Trinitarian faction of the Roman Church and so did not challenge them, and they took over after his demise. If any of this is true, I do not profess to know, but if it was, for a POD, one could have Pope Calixtus excommunicating the Trinitarians, and then have his views stick as orthodox.