Our Scripture reading today is Ephesians 4:21-24.
Verse 23, "And be renewed in the spirit of your mind;"
The renewing that the Apostle Paul refers to is not a one time renewal.  This spiritual exercise must take place on a very frequent basis.  Every day our minds are bombarded by thoughts that could be used to bring about spiritual defeat.  God has equipped us with the resources needed to process these thoughts with a renewed mind.  The very moment someone accepts Jesus Christ as their personal Saviour, they are indwelt by the Holy Spirt. The Holy Spirit is the Divine author of the Word of God.  We read in 2 Peter 1:21, "For the prophecy came not in old time by the will of man: but holy men of God spake as they were moved by the Holy Ghost."  As we read and apply the Word of God, the Holy Spirit will use God's Word to renew our minds.  Romans 12:2, "And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God."