To play devil's advocate is to argue the opposite side to test an idea. Let me play devil's advocate for a moment.
It is announced in advance, or it is simply disagreeing. The role was a real office in Rome, where a lawyer was appointed to play devil's advocate against a proposed saint.
1phraseplay devil's advocateTo argue the opposite side to test an idea.
“Somebody should play devil's advocate before we commit to it.”
play devil's advocate is a phrase.
Practised in Idioms