13 After saying that according to the apocalypse of John “the everlasting gospel” which shall be revealed in heaven as much surpasses our gospel as Christ's preaching does the sacraments of the ancient law, he has asserted what it is sacrilegious even to think; that Christ will once more suffer in the sky for the salvation of demons. And although he has not expressly said it, it is yet implied in his words that as for men God became man to set men free, so for the salvation of demons when He comes to deliver them He will become a demon.
To show that this is no gloss of mine, I must give his own words: “As Christ,” he writes, “has fulfilled the shadow of the law by the shadow of the gospel, and as all law is a pattern and shadow of things done in heaven, we must inquire whether we are justified in supposing that even the heavenly law and the rites of the celestial worship are still incomplete and need the true gospel which in the apocalypse of John is called everlasting to distinguish it from ours which is only temporal, set forth in a world that shall pass away.
Now if we extend our inquiry to the passion of our Lord and Saviour, it may indeed be overbold to suppose that He will suffer in heaven; yet if there is spiritual wickedness in heavenly places and if we confess without a blush that the Lord has once been crucified to destroy those things which He has destroyed by His passion; why need we fear to imagine a like occurrence in the upper world in the fullness of time, so that the nations of all realms shall be saved by a passion of Christ?”
Source: Letters (New Advent)