SOURCE: Stutchkoff, Der Oytser fun der Yidisher Shprakh. A mezuzah is a tiny parchment containing the Jewish prayer that begins, "Shema Yisrael." The parchment is rolled up and placed inside a case which is affixed to the doorpost of a Jewish home.
ער האָט אַזוי פֿיל שׂכל ווי אין קלויסטער מזוּזות.
Er hot azoy fil seykhl vi in kloyster mezuzes.
He has as much sense as a church has mezuzahs.