Family Matters - Season 5 Episode 22 -

When Myra presents Urkel with a nude drawing of himself, the nerd tells her to get lost. A short time later, Urkel learns that Myra is going to a convent. Concluding she is becoming a nun because he yelled at her, Urkel convinces Eddie and Waldo to dress like nuns and go to the convent to stop Myra.