Father Jack was the most memorable character on Father Ted, which Is pretty damn impressive when you consider Father Dougal, who was such a space cadet that he qualified as a sociopath. (Such a nice young man, Dougal, until you realize that he doesn't get that that other people have feelings... or lives.)
Part of what made Father Ted work was that it took ideas to extremes that most TV shows wouldn't dream of and Father Jack was nothing less than pure id wrapped up in a foul mouthed, perpetually drunk, womanizing Irish Catholic priest who is more violent than Deadpool. He was so disgusting looking that allegedly the rest of the cast wouldn't eat with Kelly if he had the makeup on.
Father Ted is a show that never fails to make me laugh and one of my secret weapons against blue, dreary days. Frank Kelly was one of the funniest parts of it. Thank you, Mister Kelly.