That truth is shield means it protects you. If truth is a shield then it protects from deception. That means deception is the ultimate attack of the devil, it is the gateway to all the expressions of the devil, in obsessions, diseases, oppressions.
The first level of deception that people faced in the bible is what happened to Adam and Eve. The devil told Eve that God is not what he claims to be, that he is different from the impression he gives. That God is a liar, that what he said is good is bad and what he said is bad is good. That deception became the gateway for the fall of man.
Jesus described the devil as the father of lies. He is the source of it, he generates it, he cannot be without it. He cannot operate without it. If he speaks lies, it is not his fault, it is his default and only setting, he cannot help himself.
And if we are wrestling with principalities and power, rulers of the darkness of this world and spiritual wickedness in high places, we should be sure that everything is mixed with lies. If the lies can be removed, nothing else can stand. After the devil is bound for one thousand years, and is released again, we are told in the book of Revelation that he will go forth once again to deceive the nations. If the devil cannot deceive, he cannot do anything. The influence he casts is deceptive influence.
It is not for fun that Paul said that the god of this world has blinded the eyes of those who do not believe, so that the light of the gospel, the truth of the gospel will not gain entrance.
If deception is so bad then truth is so good. If deception binds, truth frees. Truth shields from deception.
In the list of the armour of God, there is the shield of faith with which we quench the fiery darts of the enemy. The fiery darts comes as lies and the defense is truth, not arguments, not determination, but truth.
The one who meditates on the word day and night as described in the bible is the one who is like a tree planted by the waters. The word, the truth becomes the shield from the other negative influences in the surrounding which might hinder fruitfulness.
Truth is a defence, because “lies” is the attack, seeking to put us to bondage. There are many people captured by different lies. To others they seem free, but they are really in bondage.
For Eve, what she began to see, after eating the forbidden fruit, seemed like freedom, but that is bondage.
Guard jealously the truth you know, lest it slips away from you. What is truth may not be popular. The contention is about the truth.
Jude wrote: contend earnestly for the faith (body of truth) which was once and for all given to the saints. If he had just said contend, we will understand that the issue is serious, but he said contend earnestly. It means it is a life and death issue, it is an issue that dwarfs all others.
The bible says: do not be deceived. It means the choice is mine to be deceived or not. I am supposed to take responsibility to not be gullible.
Where I am now, the word I am exposed to may be better than what I used to hear, but to just assume that the person talking will by default be saying the truth is to neglect my responsibility to know truth by yourself.
It starts with having the love of the truth deep down in you, living without respect of persons. Because people have certain results in their lives which you desire, does not equate to swallowing what they say hook line and sinker.
It is because of this that Jesus said we should not call anyone teacher, that only one person is the teacher, Rabbi, (master teacher), and that is Christ.
We can have many good teachers, with good presentation skills, it does not make them the truth, it does not make them the Christ.
To take the shield of faith through which you quench the fiery darts of the enemy is to take personal responsibility for truth, and for not falling into deception.
You cannot because of the sweet mouth of someone, the testimonies or the proud arrogance expressed on the pulpit by someone, decide to resign the use of your brain. You will have only yourself to blame.
When you throw away your guard of truth for whatever reason, and there will be ample reason to do so as long as you are alive, you make yourself a prey, you become an accomplice in your own bondage.
The young prophet knew that the truth was to no eat anything in the place where he went to prophesy, but he allowed the pontifications of an older prophet, talking about a purported revelation from an angel, turn him away from the truth. He died, being an accomplice in his own death. He was captured by lies, when he dropped the guard of truth.
When the king asked him to eat, he held up the shield of faith. He won that context, but the devil raised the stakes, raising a prophet to lie about seeing an angel.
No wonder Paul placed a curse on anyone bringing another gospel, whether an angel, or whoever. The fight for the truth is that serious.
If you read through the book of Galatians, right from the first few verses, you can see how angry Paul was. Certain people had come with pseudo-truths and the church threw down the truth as shield and became captured by lies. They did not realise how damning their situation was, until Paul started calling them foolish, that they have fallen from grace, that they have gone back to bondage.
There is the truth about your destiny that God has shown you, you allow it to slip from you at your own peril.
John said that we do not need anyone to teach us, but we have an anointing from the holy one and we know all things. That anointing is the Spirit of truth, the same which is on Jesus, we share. So by default we are protected, just as Adam and Eve were, but you can let down your guard, like they did and lose your standing in truth, going into bondage to lies.
Don’t think you are beyond being trapped, that feeling reveals a serious vulnerability, as Paul said that he that thinketh he standeth should take heed lest he falls.