Our relationship with God changes the way we think. It's in the Bible, Romans 12:2, NIV. "Do not conform any longer to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God's will is—His good, pleasing and perfect will."
As Christians, we should have the "mind of Christ." It's in the Bible, I Corinthians 2:15-16, NIV. "The spiritual man makes judgments about all things, but he himself is not subject to any man's judgment: For who has known the mind of the Lord that he may instruct Him?' But we have the mind of Christ."
The Christian mind has the attitude of Christ. It's in the Bible, Philippians 2:5, TLB. "Your attitude should be the kind that was shown us by Jesus Christ."
The Christian mind should think about the good. It's in the Bible, Philippians 4:8, TLB. "And now, brothers, as I close this letter let me say this one more thing: Fix your thoughts on what is true and good and right. Think about things that are pure and lovely, and dwell on the fine, good things in others. Think about all you can praise God for and be glad about."