Both Grindelwald and Dumbledore used the phrase. It was even carved over the entrance to Nurmengard, the prison Grindelwald built for his enemies and where Dumbledore put him after the famous duel if 1945. Dumbledore stopped using the phrase after their falling-out, while Grindelwald continued its use.
Ye, Grinderwald... funny thing actually. I was just lectura about him on wiki yesterday cause I noticed the actor who portrays him in the deathly hallows was Jamie Cambell Bower. Who'll also be playing Jace in the movie adaptation of TMI series por Cassandra Claire =D