Never open the door to the devil. When you lose your temper you open it wide; it could not be wider. Nothing opens the door more widely than anger, and for this good reason. The moment you are controlled by your temper you are no longer able to reason, you are no longer able to think, you can no longer give a balanced judgment, for you are altogether biased on one side and against the other side. In other words, the power to reason and to think and to equate and evaluate — all that makes a man man — is gone; for the time being he is like a beast, the creature of his own passion and of an instinctive kind of power. And of course that is just the very situation in which the devil sees his most glorious kind of opportunity! It was when he persuaded Even and Adam to be angry against God that he very easily had them in his hands. He aroused in them bitterness and enmity against God, and made them believe that God was against them; and so immediately the devil could do as he liked. And think of the matter as you know it in life. Is there anything that leads to more trouble than anger? Things said in anger and in a bitter moment! — you would almost cut your tongue off, if you could, to get them back; and sometimes, though forgiven, they leave permanent wounds and scars. What havoc is wrought in the world by sinful anger!
And then a sinful anger leads to the nursing of grievances, to a desire for revenge and to have our own back; it leads us to despise people and to treat them with contempt. Sinful anger! The moment it has taken over the devil enters in. He will keep it going and insinuate thoughts and ideas and implant them. Indeed, the whole of life can be ruined just because of anger. Anger is always a cause of confusion, not only in the life of the individual but in the lives of all those who are involved in the business of living with such an individual. Nothing, I maintain, so constantly gives the devil an opportunity as loss of control in anger.
D. Martyn Lloyd-Jones, “Darkness and Light: An Exposition of Ephesians 4:17-5:17,” pg. 233-234
