Once people receive Christ, the apostle Paul fought for their mind. After the Holy Spirit has sealed your Spirit, then it is a lifetime of God’s spirit renewing your mind.
When you receive Christ you become a new creation, you are now of Christ, but you do not become a new person. You are born of His Spirit but all the past is still up here in the mind. Which is why once He saves you He then draws you into a relationship with Him where He renews your mind.
We are not talking about psychology. We are talking about exposing ourself to the word of God and allowing the Holy Spirit to heal the cortex of the brain. And changing it, putting God’s thoughts there, God’s view of life, and that is a lifetime process.