The Moving Finger writes; and, having writ,
Moves on: nor all your Piety nor Wit
Shall lure it back to cancel half a Line,
Nor all your Tears wash out a Word of it.

Omar Khayyám (1048-1123) Persian poet, mathematician, philosopher, astronomer

Rubáiyát, 71 [tr. FitzGerald]

A reference to Daniel 5 in the Bible.