Deceit means misleading, deception, not honest.
Perverse means turned from the truth, contrary to the evidence.
When you speak words according to how you feel or by what you see, you will be speaking words of deceit and perversity when they are held up against the evidence of God's Word. When you speak words according to the Word of God, and disregard your physical senses, you are speaking the Truth according to God, but to those around you, you sound as if you are being deceitful and perverse in what you are saying.
What you use as your evidence in what you believe is what makes your words either true or deceitful before God and man. When I declare God's truth in a situation before me, it will be the truth before God, but it may look deceitful to a man that does not no God's way. The Bible calls this man a carnal man. His mind has not been renewed to the ways of God so he thinks like a natural worldly man instead of a born-again spirit man. Natural (carnal) man measures truth by his physical senses, so what he thinks about it is elevated to the place of truth. The born-again man measures truth by what God has said in His Word, for His Word is Truth (John 17:17).
Whatever you choose to use as your evidence of what is true will determine whether the words out of your mouth are perverse and deceitful or true. If God's Word is your standard of truth, then what God says is true over what you see, feel, or think about it. When you say what God says over contrary evidence in the physical realm that stands before you, you are exalting the evidence of God's Word above the physical evidence that is seen. To the man of faith who believes God's Word, when he speaks God's Word over contrary circumstances and situations before him, he is speaking the truth before God and is agreeing with God, but that same word of truth before God looks deceitful before a man that does not know the ways of God.
To the natural/carnal man, the words of faith sound and look to him like a lie, because what is said does not agree with what he sees and this man exalts his evidence above the man of faith's evidence, and he calls the man who lives by faith a liar and being deceitful.
In reality both men are right according to the evidence they use to determine the truth. They are both deceitful in each others sight. Here in lies the conflict between the natural/carnal man and the man who is led by God's Spirit, the spiritual man. In the realm they choose to live in, both are right. But there is a way that seems right to a (carnal)man, but the end of that way is death (Prov 14:12). But to the (born-again) spiritual man the Word of God leads him to life. A man's choice leads to life or death (Deut 30:19). When the born-again spiritual man chooses God's Word over his physical senses, it's the way of life for him.
So how do you know if your words are deceitful or perverse? Only one way. Who does your words agree with? What God says about it, or what the natural circumstances are saying to you. Depending on where you live your life, spiritual or natural realm, this will dictate to you whether the words you hear out of your mouth are deceitful and perverse or true. The carnal man thinks the spiritual man is lying, but the spiritual man is doing nothing more than agreeing with his God rather than agreeing with his physical senses. This looks foolish to the carnal man because he depends on his natural senses to determine the truth.
Now I said a lot to say this, that to live by faith in what God says over what your physical senses are telling you is the way God designed His man to live, but sin entered the first man when he chose what he saw over what God said about it, and man exalted himself and his physical senses over God's Word, and that conflict will be played out until the return of the Lord Jesus.
God sets before man, life and death, blessing and cursing (Deut 30:19). God says, "choose life" (just for those who don't know the right answer). You make that choice by choosing His way to live your life and His way is, "the just (the born-again man) SHALL live by FAITH" (Heb 10:38), therefore if you choose life, then you are choosing the life of faith, and using God's Word as your evidence in every situation you face in life, and saying words out of your mouth that agree with what God says about it. They will be true words in the hearing of God, and deceitful words in the hearing of carnal man, but that word you speak will be life unto you and health and medicine to all your flesh (Prov 4:22).
Let God be true and every man a liar (Rom 3:4), for when a man says words that don't agree with what God has said, then God calls this man a liar and the end of that man's words are death. Now he might look good before other carnal men, but he looks like a fool to God.
Be in agreement with God and His Word today. You may look like a fool before carnal men, but you will look right and perfect (complete) before God and you will live long on the earth (Ps 91:16) and forever with God throughout eternity.
Now that sounds like a choice every man should make. Make the choice to live by faith and please the God (Heb 11:6) who created you and desires to walk and live with you forever.
The just shall live by faith. Are you up to it? After what you have just heard in this writing, how could you not? God calls those things which do not exist as though they did (Rom 4:17). If you are going to live by faith, you are going to have to take after your Father and further more, if you are His son, then He expects you to.
Keep the faith and be blessed.
