These are of some antiquity:

O Christmas tree, O Christmas tree,
O piss on thee, O Christmas tree!

*

While shepherds watched their flocks by night,
All shitting on the ground,
An angel of the Lord came down
And handed paper round.

*

Hark! The herald angels sing:
Beecham's pills are just the thing,
Move you gently, meek and mild,
Two for adults and one for child.
Regular administration,
Just the thing for constipation.
How can man to art aspire
If his soul is not on fire?
How can man crawl into bed
With his belly full of lead?