Once, when my siblings and I were little, the minister in the church told us it was time to sing Joy to the World. At the time, my dad was in a rock band, and they did the Three Dog Night song of the same name. So, my sister, excited that she knows the words to Joy to the World, starts rockin' out in the aisle, at the top of her lungs... "Jeremiah was a bullfrog! Was a good friend of mine."
My embarrassed parents tried to hush her, but the congregation was already laughing. This was the old time Missouri Synod Lutheran Church-- the one where you wouldn't even dream of clapping in church, let alone singing some rock song and dancing in the aisles. The minister said something about maybe doing the Christmas Joy to the World instead. The organist took over, and my sister fumed... she liked the other one much better.
We sang Joy to the World tonight in the candlelight service. I tapped my sister, who is 35 now, on the shoulder to make sure she knew which version we were singing. She called me a smartass... in church, no less! ;-)