As believers, we should understand that in this life, we have God and the arch enemy of God, and there are two things we can do: what is evil or what is good the choice is ours because we have the freedom to choose between good and evil. God created us and give us the freedom to choose between good and evil, obedience and disobedience, so the choice is ours to choose good or evil.
The brain is just like the computer programmer, what is in the computer depends on the programmer of the computer, it does not have information unless there's a human being that encodes all those things in it. This means that the brain controls and determines what happens in the human body, just as a programmer controls and determines what a computer does. Our body cannot function without the brain, all the characters and our manner of life is been regulated by the brain. This means that we are fully in control of our manner of life; our attitude, and personality depends on the decision we choose. As christians, we have two choices: Blessing and cursing. We have freedom to choose either good or bad and that's why as christians, we have to be careful in everything we do and the information we listen to as those things can influence our brain thereby making us to behave in a way that will not please God.
No one can easily scrape out every evil untill the judgement day, that's why we are living in a world wherein humans have their own preferences and choices in life. But in as much as we are given freedom of choice, let's always choose good, be a peacemaker and live righteously because we will give account on the judgement day on how we live our lives here on earth.
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