Renovation of the Heart; Putting on the Character of Christ
The ideal end of Christian spiritual transformation is when all of the essential parts of the human self are effectively organized around God, as they are restored and sustained by Him. Spiritual transformation in Christ is the process leading to that ideal end, and its result is love of God with all of the heart, soul, mind, and strength, and of the neighbor as oneself.
You can experience significant growth in your Christian walk, shed sinful habits, and increasingly take on the character of Christ. Willard calls this "the transformation of the spirit"—a divine process that "brings every element in our being, working from inside out, into harmony with the will of God or the kingdom of God."