Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things. Philippians 4:8
Stop for a moment to consider that God tells us what to think about.
If anyone else told you what to think about, I am sure you would object. Our mind is our own is it not? We may subject ourselves to the laws of the land, or follow the advice of others on how to act. But our mind is our own domain. Right?
Anyone in advertising or marketing knows how silly this is. The mind is very easy to manipulate. All you need is the internet feeding people media that implants values and ideas. Why do ads exist? Because they work. They get people to buy products.
The difference between the way God influences our minds and the way the world does, is that God is honest about it. He tells us up front, through his servant Paul, that we are to choose what we think about, and to choose the right things.
The world tries to sneak thoughts into our heads through the media we consume, or through the cultural ethos of the day.
So, God tells us to fill our minds with good things (truth, honor, justice, purity, loveliness, excellence etc.). When our minds are full of these things, there is little space left for evil thoughts to creep in from the world around us, or from our own hearts.