And be renewed in the spirit of your mind;
Note 14 at Eph 4:23: The word "spirit" here is not designating the Holy Spirit or even the born-again spirit. In fact, it is not referring to a part of us at all. It is speaking of our attitude. The New International Version translates this as "to be made new in the attitude of your minds." Strong's Concordance says that the Greek word "PNEUMA," which was translated "spirit" in this verse, can mean "mental disposition." That's the way it is used here.
Paul was saying that we have to not only reprogram our minds with new information but also allow these new truths to change our attitudes. Synonyms for "attitude" are outlook, feeling, sentiment, and disposition. Our perspectives have to change.
Many people have heard biblical truths and can recall them, but often they don't dwell upon them to the degree that those truths change their attitudes. For instance, they can know that it is God's will to prosper them financially, but if they don't start seeing themselves with their needs met, then their attitude hasn't changed. A poverty attitude will cause them to stay poor even though they know God wants them to prosper.
So, it is not good enough to just learn facts from God's Word and store those facts so that we can recall them. We have to meditate on the truths of God's Word until our outlook, feelings, sentiments, and dispositions have been renewed to God's way of thinking.