“Be patient,” said he, “and of good understanding, and you will rule over every wicked work, and you will work all righteousness. For if you be patient, the Holy Spirit that dwells in you will be pure. He will not be darkened by any evil spirit, but, dwelling in a broad region, he will rejoice and be glad; and with the vessel in which he dwells he will serve God in gladness, having great peace within himself. But if any outburst of anger take place, immediately the Holy Spirit, who is tender, is straitened, not having a pure place, and He seeks to depart.
For he is choked by the vile spirit, and cannot attend on the Lord as he wishes, for anger pollutes him. For the Lord dwells in long-suffering, but the devil in anger. The two spirits, then, when dwelling in the same habitation, are at discord with each other, and are troublesome to that man in whom they dwell. For if an exceedingly small piece of wormwood be taken and put into a jar of honey, is not the honey entirely destroyed, and does not the exceedingly small piece of wormwood entirely take away the sweetness of the honey, so that it no longer affords any gratification to its owner, but has become bitter, and lost its use?
But if the wormwood be not put into the honey, then the honey remains sweet, and is of use to its owner. You see, then, that patience is sweeter than honey, and useful to God, and the Lord dwells in it. But anger is bitter and useless. Now, if anger be mingled with patience, the patience is polluted, and its prayer is not then useful to God.” “I should like, sir,” said I, “to know the power of anger, that I may guard myself against it.” And he said, “If you do not guard yourself against it, you and your house lose all hope of salvation. Guard yourself, therefore, against it. For I am with you, and all will depart from it who repent with their whole heart. For I will be with them, and I will save them all. For all are justified by the most holy angel.”
Source: The Pastor (or "The Shepherd") (New Advent)