Ephesians 4:21-23

If in fact you have [really] heard Him and have been taught by Him, just as truth is in Jesus [revealed in His life and personified in Him], that, regarding your previous way of life, you put off your old self [completely discard your former nature], which is being corrupted through deceitful desires, and be continually renewed in the spirit of your mind [having a fresh, untarnished mental and spiritual attitude]