Revelation 12:9 - Wesley's Explanatory Notes

And the great dragon was cast out — It is not yet said, unto the earth — He was cast out of heaven; and at this the inhabitants of heaven rejoice. He is termed the great dragon, as appearing here in that shape, to intimate his poisonous and cruel disposition. The ancient serpent — In allusion to his deceiving Eve in that form. Dragons are a kind of large serpent. Who is called the Devil and Satan — These are words of exactly the same meaning; only the former is Greek; the latter, Hebrew; denoting the grand adversary of all the saints, whether Jews or gentiles. He has deceived the whole world — Not only in their first parents, but through all ages, and in all countries, into unbelief and all wickedness; into the hating and persecuting faith and all goodness. He was cast out unto the earth — He was cast out of heaven; and being cast out thence, himself came to the earth. Nor had he been unemployed on the earth before, although his ordinary abode was in heaven.