Christianity as a specific doctrine was slain with Jesus, suddenly and utterly. He was hardly cold in his grave, or high in his heaven (as you please), before the apostles dragged the tradition of him down to the level of the thing it has remained ever since.
Where is Polonius? HAMLET In heaven. Send hither to see. If your messenger find him not there, seek him i' th' other place yourself. But if indeed you find him not within this month, you shall nose him as you go up the stairs into the lobby.
The way of Heaven and Earth may be completely declared in one sentence: They are without any doubleness, and so they produce things in a manner that is unfathomable.
If a thing happens once, it can happen again. If any human being has ever realised perfection, we too can do so. If we cannot become perfect here and now, we never can in any state or heaven or condition we may imagine.