As believers, we must be very conscious of what enters into our hearts because whatever we express outside is what is already in our hearts.
Without a good heart, it is impossible to do good. And if we don't have a bad heart, we cannot be capable of doing bad things. If you see a person acting in a bad way, know that his or her heart is already corrupt.
Proverbs 4:23, the book says, Keep thy heart with all diligence, for out of it are the issues of life. Believers must guard their hearts. A good mind would always want to do good things. While a corrupt mind would always want to do corrupt things.
When we have a good mind, we will be willing to do the good will of God and not hurt people or engage in all kinds of violence that you see today.