good observation John-Mann ,why on earth would Jesus preach the good news to demons ? The Greek word for good news is (ev-aggelion) whereas preaching the good news (ev-ag-ge-li-zo-mai') .Peter used none of these words instead he used the word Ke·rys′so, in general, means “proclaim” (good or bad news), as distinguished from eu·ag·ge·li′zo·mai, “declare good news.” Noah was a preacher (or herald, ke′ryx) to the antediluvian world, warning them. (2Pe 2:5) Christ preached (like a herald) to the spirits in prison, but not the good news.(1Pe 3:18, 19).What was preached to “spirits in prison” must therefore have been a message of judgment .
All these observation are part of my original post :