The Adoptionists held that it was a confusion of the two natures in Christ to say that Christ was proper and real Son of God not only in his Godhead but in His whole Person. The highest that could befall humanity, they maintained, was to be adopted into sonship with God; therefore Christ’s humanity is adopted into sonship. This adoption had three stages they said; the first at the moment of conception, the second at His baptism, the final stage at His resurrection. The Adoptionists professed to deny that they were Nestorians, that is, that they divided Christ into two Persons; but it was urged against them that if they did not divide Christ into two persons, their theory did, when it was pressed to its necessary consequence. That is the history of the origin of many of the heresies.
Various measures had been taken against the heresy of the Adoptionists, both by Karl and by the Pope, Adrian. In course of time Karl sent the treatise of Felix to Alcuin, who was at the time in England, and Alcuin returned to France, never again to visit his native country. Simeon of Durham tells us that the English bishops made him their representative for the refutation of Felix. As such, probably, in part, but also by the special wish of Karl, he attended the Council of Frankfort in 794, and though only a deacon, argued against Felix. Felix was condemned. Alcuin’s argument was at Karl’s request or command developed into a treatise in seven books; and he wrote also a treatise in three books against Elipandus.
We have these ten books. They fill 220 very closely printed columns in Migne’s series. The books against Felix are among the best and most independent of Alcuin’s dogmatic work.
This by no means ended the matter. In the year 798 Karl sent to Alcuin a treatise by Felix, which he desired Alcuin to refute. Alcuin’s reply has been the subject of so much controversy that it will be well to give it as literally as possible. The point is, the place assigned to the Pope as a judge of doctrine. I only quote that part of the very long letter.
Ep. 100. July, 798.
“I beseech you, if it please your piety, that a copy of the treatise be sent to the apostolic lord [that is of course the Pope] and another to Paulinus the patriarch [of Aquileia]; similarly to Richbon [of Trèves] and Theodulf [of Orleans] bishops, doctors, and ministers; that they may (singuli) severally answer for themselves.[168] Your Flaccus [Alcuin] labours with you in giving account of the catholic faith. Allow him sufficient time to consider with his pupils, quietly and carefully, the opinions of the Fathers, what each has said on such views as this subverter has set forth in his book. Then, at a time appointed by you, let the answers of the above several persons (singulorum) be brought to you. And whatever of opinion or of meaning in that book is found to be contrary to the catholic faith, let it be overthrown by catholic quotations. And if the writings of all [of the above] sound forth equally and concordantly in profession or defence of the catholic faith, it will be clear that one spirit speaks through the voice and heart of all; but if anything diverse is found in the words or the writings (dictis vel scriptis) of any one of them, let it be judged which is most in accord with sacred scripture and the catholic fathers, and give the palm to him who is most firm in the divine evidences.”
It seems to be perfectly clear that Alcuin’s plan was that he and his students should draw up a chain of passages from the Fathers, such as that which at an earlier stage he had himself sent to Felix;[169] that in this way they should spend the time till Karl had got answers by letter, or by the mouth of a messenger, or even at a personal interview, from each of the four, Pope, patriarch, and two bishops; and then that all the answers should be tested by the passages extracted from the writings of the Fathers. There is not the slightest sign of Pope Hadrian having a preponderant voice, or a voice on a doctrinal question more authoritative than that of the learned Bishop of Orleans. But if, as the Roman controversialist endeavours to maintain, the Pope was not included in the curious competition, and only the three others were to be counted, that is worse still for the position of the Pope; for Alcuin and Karl were to settle the matter without paying any attention to the Pope, indeed without considering anything that he might say. The Roman controversialist has to play tricks with the punctuation and with the Latin to separate off the Pope from the patriarch. There was no punctuation[170] in the letter, we must suppose; those who wrote in Latin as good as Alcuin’s could make a sentence clear in its meaning without commas and semicolons; and if the passage is read without stops the Pope is included, as he is also with any punctuation other than that of the Roman controversialist. But, as I have said, if he was included with the other three he was given a full chance of making his opinion felt on equal terms with that of each of the others; if he was not included, the verdict was to be final without him.
Ep. 11. July, 786.