Who Pisseth against the Wall?

David R. (that’s as much of his last name as he cares to disclose) writes:

I’m a Greek and Latin philologist currently teaching himself biblical Hebrew (a lifelong dream). I wonder whether you’ve ever written about the unclear biblical idiom “who pisseth against the wall.” Thank you in advance for your delicious word-nerdery.

You’re certainly welcome, Mr. R., and I’m glad you asked. “Who pisseth against the wall,” which is the King James Version’s rendering of the biblical Hebrew’s mashtin b’kir, is an expression I’m fond of, not only because of its pungency but because it once caught the New York Times napping.