G. Reale, A History of Ancient Philosophy: The Systems of the Hellenistic Age, trans. John R. Catan (Albany: State University of New York Press, 1985) 374.
Epicurus said that if a philosophy is not able to treat some passion of the human soul, it is useless. All the Hellenistic philosophers agree with this statement. In conclusion, these philosophical schools understood, as few others, that the affections of the soul undermine the happiness of men. Concordantly, these Schools also understood that passions are not cured or softened by giving vent, since the venting increases and makes them stronger. Consequently, they understood that the venting of the passions cannot bring happiness, precisely because the vented passion generates further and more impelling passions or, at the most, venting gives only a brief respite, preparing for a further outbreak, but never for peace of the soul. Therefore, the remedy can only be a radical reduction of passions or even their elimination and total emptying. Peacefulness and calm have to be found in the elimination of the passions, and happiness is peace of spirit.
The Hellenistic philosophers desired the same thing that I do: to keep my passions in check. I'm not sure if I'd go as far as some of them (e.g., ascetics), since I see nothing wrong with enjoying the fine things of life. But I know that my passions of hatred, fear, worry, jealousy, etc. hinder me from being happy.
And much of the Bible has the same message. In the Old Testament, we see the bad consequences of hatred and jealousy, both for the ones who have those passions and the people around them. I think of Joseph's brothers and King Saul. Lust also tripped people up, as was the case with Shechem, David, Samson, and Amnon. People can easily lose their heads when they are controlled by passion!
In the New Testament, Christians are offered the hope that they can subdue their sinful passions and bear the fruit of the Spirit (Romans 6:12; Galatians 5:17-24; Ephesians 2:3). And a life of the Spirit is one of peace. I like the NRSV translation of Romans 8:6: "To set the mind on the flesh is death, but to set the mind on the Spirit is life and peace."
Reale says that the Hellenistic philosophers were skeptical about "venting" the passions in an attempt to subdue them. I'm not entirely sure how he defines "venting." Does he mean the "m" word? Is he referring to "venting" anger--through hitting a tree, shouting in private, etc.? If so, then I can agree with the Hellenistic philosophers that "venting" only subdues the passions for a little while, rather than eliminating them completely.
These days, people are encouraged to vent. Christians like to point to the Psalms, in which King David expresses frustration with God. At an Assemblies of God church I once attended, a guest speaker was talking about the importance of venting in prayer. According to him, we need to be honest with God about what bothers and hurts us, then we can fill our empty jars with wholesome things.
Ron Dart used to say that we shouldn't be afraid to tell God that we hate him or somebody else, since God already knows. According to Dart, as we tell God to break someone's teeth, we come to the realization that God may not want to punish a person just because we are mad at him. Some of us need to release our anger before we can arrive at this insight.
Dr. Phil tells angry people to express their anger to God, since God can "take it." Otherwise, our anger can pop up in unexpected places and hurt someone.
Therapists encourage people to vent their anger rather than denying it. See my post, Reactions to Sybil (2008).
I'm not for pretending as if my anger does not exist. Venting does help me to release it. But, as the Hellenistic philosophers note, the release is only temporary. Before you know it, I'm at the prayer altar once more, releasing the exact same anger that I had prayed about the day before.
Venting may not be the way to release anger permanently. Perhaps other things should come into play: understanding someone else's perspective, asking about my part in the conflict, new and objective ways of looking at the situation, etc. That is why Alcoholics Anonymous emphasizes the fourth and the fifth steps: We write down our resentments and how people have hurt us (e.g., our security, our financial situation, etc.). Then, we share our resentments with another human being and get a fresh way of looking at the situation.