Updated: May 20, 2019
In beginning of the cooking process, meat is originally bland and tasteless, basically a blank slate. But in the long run, it is what you put in it that will give it its flavor.
When you marinate Meat, at first, it doesn't have much taste. But when you marinate the Meat in the watery spicy mixture or sauce, and it soaks for an extended period of time, the flavor of the Meat changes because the spices have gotten into it. The same thing happens to you when you let anger, bitterness, unforgiveness, rage, jealousy, etc, and any negative emotions sit in your heart for a long time. When you feel these emotions in your heart and you do not deal with them (find a way to get rid of them) immediately, they sip into you and get their roots in you and over time, it becomes hard to get rid of them. The longer they sit in you, the harder it is to get rid of them, and the greater the damage they cause will be.
So here's my advice: Don't allow anger or any negative emotions to marinate in your heart because it will really set in and the damage will be very hard to reverse. Its Human to feel. It's okay to feel hurt, sadness, rage, anger, bitterness, etc. But it becomes a huge problem when those issues are left unchecked. Feel, then let it go.
If you have to literally speak out loud and say, "I forgive, i let go of this hurt, i refuse to be mad any longer, i won't be bitter anymore, etc," whatever you have to do to be free, do it. And take an active step to seeing that fulfilled in your heart. Keep your emotions in check and refuse to go back to that place.
You are in control, not your feelings.
Let go. Forgive. Move on. Be Free.
And only allow good, positive, encouraging things, to sit, grow, and marinate in you.
But most importantly, develop the Fruit of the Spirit. You are a much better version of yourself, and a more enjoyable person to be around when you have the Fruit of the Spirit in you.