What We Need to Know About the Lord's Coming

I'm currently learning a lot in a fascinating theological school class about what the Lord did while He was in the world but even though we read a lot in the Heavenly Doctrines and read papers by people who have studied various topics extensively and also spend a long time discussing things we still regularly run into things that are beyond our ability to understand. As a result I find it helpful to keep passages like Arcana Coelestia 1676:2-3 in mind.

He to whom it has not been given to know heavenly arcana, may suppose that there was no need of the Lord's coming into the world to fight against the hells, and by means of temptations admitted into Himself to vanquish and conquer them, when they might have been subjugated at any time by the Divine Omnipotence, and shut up in their hells; but that still the fact is really so, is a certain truth. To unfold the arcana themselves merely as to the most general things would fill a whole work; and it would also give occasion for reasonings about such Divine mysteries as human minds would not comprehend, however fully they might be unfolded; and most people would not desire to comprehend them.

Therefore it is sufficient for men to know, and, because it is so, to believe, that it is an eternal truth that unless the Lord had come into the world and subjugated and conquered the hells by means of temptations admitted into Himself, the human race would have perished; and that otherwise those who have been on this earth even from the time of the Most Ancient Church could not possibly have been saved.