The Heart is like a fuel tank, that you always have to keep filling up with Imaan
Forgiving someone isn't just about doing good to another. It's also about healing a scar in your own heart.
You train your heart to control your body. That's what you do when you fast.
Your relationship with Allah, depends on the heart being clean.
A single word that can be offensive to someone is a horrible thing for anyone who has iman. In other words, filthy language out of your mouth and faith inside your heart cannot coexist. You cannot have iman in your heart and ugly words come out of your mouth. If you have no control over whatever four letter words you keep using every time you get frustrated, there's a spiritual problem, it's not just a habit problem. How can you use a terrible word for anyone who has iman?
If shaytan has entered into your heart - evil will look beautiful to you and good will seem tiring and exhausting.