The beautiful fight and the full reality of grace

I am reading 'The Beautiful Fight' by Gary Thomas. This book is packed with insights and food for thought. In Chapter 8 the author writes about setting our minds on God. He stresses that we are in control of our minds and that our will can be stronger than our emotions and passions - if we allow God's Spirit to guide us.
"Neurologists tell us a startling truth that has major implications for spiritual formation: Our choices and experience shape our brain, both literally and physiologically. What we choose cognitively helps make us into who we are. (...) In a neurological sense, our character is the sum total of the moral decisions we have made. In a theological sense, our behavior and our thinking are interconnected. Here's how the apostle Paul describes it: Those who live according to the sinful nature have their minds set on what that nature desires; but those who live in accordance with the Spirit have their minds set on what the Spirit desires. The mind of sinful man is death, but the mind controlled by the Spirit is life and peace; the sinful mind is hostile to God." (The Beautiful Fight, p. 110)

Another quote that I want to share with you: "I have seen men who don't practice holiness start preaching nothing but grace - forgetting all about real change and transformation. I have also seen men who are deeply convicted about unrepented sin preach with anger and venom, forgetting all about forgiveness and mercy. Both camps miss the totality of God's grace, because they see it from only one side. They are led into either misunderstanding forgiveness, which exalts 'tolerance' over transformation, or misunderstanding God's judgment, which leads only to condemnation. Because their souls have grown weak, their minds can't grasp the full reality of grace that pardons and transforms.
What we do affects how we think. There is no getting around this truth. Right living supports right doctrine; right doctrine helps us to keep living right. We desperately need both." (The Beautiful Fight, page 111)