A smiling face, a humble attitude need not be the reflection of the real person inside, however when all this can be held/ hidden from fellow men nothing can ever be hidden from God, for God knows the very intent of our hearts, He knows our very being perfectly.
Paul bluntly stated the truth of our carnal mind when he said...
"Because the carnal mind is enmity against God; for it is not subject to the law of God, nor indeed can be." Romans 8:7 (NKJV)
Thus, when in our carnal mind, we are actually knowingly/unknowingly in a state of enmity with God.
Would you ever be happy to meet a person who when in your presence act to be really good, however you surely know that on many occasions he has and continuous to work against you?
So are we in the presence of God when we beautifully sing praises to God and utter well worded prayers in the church, however our personal life is fully of carnal thoughts and deeds.
We can never be what we are pretending to be before God, for before God all is as it is, we are as we are.
Thus, now if we have not seriously thought about correcting our carnal mind and have never taken so seriously the consequences of this, then we need to do it right now.
An enmity with God that which is a carnal mind, can never exist much longer, its best for us if can understand this and correct ourselves.
In yet another verse Paul exhorts us to do this....
"And do not be conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God." Romans 12:2 (NKJV)
and also this we need to do...
"I beseech you therefore, brethren, by the mercies of God, that you present your bodies a living sacrifice, holy, acceptable to God, which is your reasonable service." Romans 12:1 (NKJV)
Yes!!! We need to present our whole person before God as holy and acceptable, thus let's get rid of all our carnal thoughts with the help of God and be a faithful friend of God and He is to us.