The ways Bitterness causes trouble for us.
According to my mother, the answer is "YES"! One time I asked her why she was so mad and she genuinely answered, "I am not mad just frustrated. Christians do not get mad."
To me, the "frustration" of a red haired Irishwoman looked a lot like mad!
Is that what the Bible teaches about emotions we call anger? Well, no. In Ephesians 4:26, St. Paul, from a psychological sense, wrote some incredibly insightful statements about relationships. He said: "You can be upset and angry but be careful and do not sin or "miss the mark" with that dangerous feeling.
He added, "Do not let the day pass and a spirit of bitterness overtake you." These are two completely different terms and they have very different consequences. The first means angry feelings that spill out suddenly. That happens and we cannot hide it. It can assist us in dealing with a COMPLAINT.
The second term "bitterness" means means "A settled mindset of demanding punishment from the object of your feelings."
Paul was very well acquainted with feelings of anger and bitterness. I think it was his "Thorn in the flesh." He wrestled with it for a long time.
So, to summarize, feelings of hurt and anger are normal and placed in us by the Spirit for protection. It brings the fight or flight impulse that can save us from danger when we automatically react to a threat without thinking.
Bitterness is a longer term issue that eats us up inside. This is great psychology and ministers life to the psyche or soul. Read my books on thoughts and feelings.