“and have put on the new man, who is being renewed in knowledge after the image of his Creator,”
The old man, or the old life of self and sin has gone, and the new life in the Spirit has come. The presence of the Holy Spirit in the life of a person makes all the difference. The old life has been crucified with Christ and the new life is now lived by the power of God. The old life is dead in the grave and the new life is risen with Christ as a new life in God.
The Christian life is a constant putting off of the old self and putting on the likeness of Christ. It is a daily walk with God, becoming more like Him and learning His will and purposes for our life. We are renewed daily in the knowledge of God, what He is like and what he requires of us.
As we live from day to day in the attitude of compliance to the Lord, we learn to be like Him and to love Him. It is not a cold copying exercise, but the heartfelt following of the example of Christ and the true love of longing to be like Him. All other loves are put to flight as we focus our mind and attention on Him and succumb to His beauty and glory.
People are made in the image of God, and though we may be fallen and fail often, we can be made new in the renewing of our minds towards the Lord.