In a letter, the mathematician Abel wrote
Les séries divergentes sont en général quelque chose de bien fatal et c’est une honte qu’on ose y fonder aucune démonstration.
In the book NIELS HENRIK ABEL and his Times: Called Too Soon by Flames Afar by Arild Stubhaug, on page 343, Abel's quote is translated as
On the Whole, Divergent Series are the Work of the Devil and it's a Shame that one dares base any Demonstration upon them.
But the Wikipedia article on divergent series instead translates Abel's quote as
Divergent series are in general something fatal, and it is a disgrace to base any proof on them.
Is "work of the devil" a reasonable translation? Is the expression idiomatic?