This was during one New Year's Eve service. When midnight hit, everyone got up to hug and say "Happy New Year" to each other. I saw my peer Brother K and decided to say "Happy New Year" to him in Cantonese, just for fun.
"Gong hay fat choy!"
Brother K, whose last name happens to be Choi, abruptly stopped and said indignantly, "Hey! Who you calling a fat Choi!"