Never take the antidote before the poison

Are you expecting someone to poison you?" he said, somewhat taken aback.
"Not really. But it seems to me that if you wait around until you know you need an antidote, it's probably too late to pick one up.

There's a Bible on the shelf there. But I keep it next to Voltaire-poison and antidote.

Malice drinketh its own poison

Danger can never be overcome without taking risks

Even the just may sin with an open chest of gold before them