Holy imbecile tender and mild

The story:

I was perhaps seven years old and was in church at Christmas
standing next to my nasty, mean sister-in-law singing along when
I uttered the fateful lyrics. She whacked me on the side of the head
and scolded me for singing those bad lyrics in house of the Lord. I
didn't have the nerve to tell that's how I learned them. I did notice,
for the first time, the correct lyrics in the hymnal. I was rubbing
the sore, freshly whacked side of my head but nevertheless
laughing to myself a little bit