There are many verses about the mind, thinking, and our thought life. So many I am sure books have been written about this subject. (I've not looked into that, these are just my thoughts that stemmed from reading that verse.)
I've longed believed that people can get mentally stuck when they have some type of emotional trauma. For example, if a young girl loses her mother at the age of 12, she'll tend to emotional stay as a 12 year old. If a person doesn't work towards emotional maturity after emotional trauma they can emotionally stay at the age of the incident. (This is just Heather's theory.)
In the years that I first thought about this concept it's proven itself in many people. (I guess you can say I enjoy the study of people.) I've seen someone who had a trauma at the age of 7, emotionally respond in a pressure situation at the age of 35 like a 7 year old.
We're told over and over in scripture to "renew our mind" (Rm. 12:2) "take captive our thoughts" (1 Cor. 10:5), let the Lord "search our mind" (Jer. 17:10), "prepare our minds" (1 Pet. 1:13) and we're told to have a "sound mind" (2 Tim. 1:7).
Much of our Christian walk starts in our mind and in our thoughts. How crafty is satan then to attack us in our thoughts. To make it much easier to stay mentally immature than to grow towards being mature in our thinking. Obvious if Paul felt this was important enough to tell the Corinthians (who were having church unity issues) it is something that is key and helpful in our growth as believers.
What do you think of this concept? How do we grow in our thinking? (Maybe we'll all add to another blog post about this.)