Believing a lie is the genesis of sin, and it hardens our heart. Hardness of heart leads to an increasing futility of mind, which leads to more corrupt practices. Even Christians can have this happen to them, we all do to a certain degree. Paul is saying we should strive to make it happen less, stop believing lies and start embracing the truth, dance with it instead of dancing with the devil. This whole passage from Ephesians 4 is about the truth and learning to trust and obey it, which becomes an easier thing to connect with when we discover what lies we are believing. Usually they are about the fear we have of letting something go and embracing something else because we haven’t ever done it that way before.
We are both loving truth and trying to stamp out sin or we are living in lies and loving our sin. The deceitfulness of sin is what hardens your heart which leads to the darkness of a futile mind where we think we are doing good but we are not, we are only doing it the way we want to and only obeying in the way that appeases our own undeveloped or underdeveloped conscience. This has many disastrous effects. If we continue to love a lie, we do more than believe lies, we become hardened in our hearts and we actually cherish the lies, we cherish the sin; we love our false doctrines, and our pet theologies. We also are prone to believing more lies, like believing that we are hearing from God or that we discern some teaching as true or false doctrine when we don’t have any scriptural support. We just trust our feelings without any basis in bible facts.
The word of God must be the arbiter; we must evaluate teachings based on the plumb line of the bible. Pagan practices have made their way into the church, and false teaching breeds false believers. Unfortunately, when confronted lovingly with bible truth, many people would simply rather believe a lie than lose face or submit their will. It comes down to a case of “My judgment is superior to yours”. They may say, “God told me you are wrong”, or “I have the gift of discernment”, or “You are just all about head knowledge”, or use the pragmatic yardstick – “look at all the fruit”, and on and on it goes.
Until the believer believes the Word enough to submit his heart, mind, and will to its authority nothing of great value can be accomplished. As long as the opinions of the believer reign supreme the person teaching them cannot take him anywhere. Worst of all are the instances where the person believes he has received a “personal” word from the Lord and uses it to justify himself. The pastor or teacher or discipler will subsequently find that he cannot lead this person down the road of obedience. As Jonathan Edwards observed, “As long as a person has a notion that he is guided by immediate direction from heaven, it makes him incorrigible and impregnable in all his misconduct.”
We must always be willing to learn and turn if we can be shown clearly from scripture and plain reasoning that our position is wrong. Renewing your mind means changing it. Stop believing the lies and start believing the truth as we see so clearly in this whole passage. Put on the new you which is the true you who believes in truth. Church should be a place where everyone tells the truth in a safe environment for the people and a deadly environment for lies. Speaking the truth in love so as to grow up means we don’t let it just go. We should live in fear of accepting error. We must confront error when confronted with it. If we love the truth we won’t stand for living with lies.