When evil thoughts come…
A brother came to Poemen and said to him, “Many thoughts come into my mind and put me in danger.”
He sent him out into the open air, and said, “Open your lungs and do not breathe.”
He replied, “I can’t do that.”
Then he said to him: “Just as you can’t stop air coming into your lungs, so you can’t stop thoughts coming into your mind. Your part is to resist them.”
– De vitis Patrum, Sive Verba Seniorum, Liber V