If we take St Paul literally, then we are not allowed to cling to our anger for even a day (cf. Eph 4.26). I would like to make a comment, however, that many people are so embittered and furious when they are in a state of anger, that they not only cling to their anger for a day, but drag it on for weeks. I am at a loss for words to explain those who do not even vent their anger in speech but erect a barrier of sullen silence around them and distill the bitter poison of their hearts until it finally destroys them.
— Saint John Cassian (c. 360-435)
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