“errare humanum est perseverare diabolicum” attributed to Seneca the Younger

“To err is human, to persist is of the devil”
“It is human to err; it is devilish to remain willfully in error”
“To err is human, to persist in error beastly”

Other Variation(s):
Cuiusvis hominis est errare, nullius nisi insipientis in errore perseverare.

Please add other translations of this phrase in the comments sections.