"Foolish hearts and lying tongues cannot be part of your association or interaction one to another. Both must be far removed if you desire My presence. You must consider the horrible impact of these acts. A foolish heart minimizes the importance of those things that are important to Me. It denies biblical truths and sways others to live for themselves, not for the glory of Jesus. A lying tongue kills the truth. It murders the wealth of My Holy Spirit, separates My children, and destroys the trust, one to another, that is needed if you are to move with Me.
"Get rid of these elements in your fellowship. Get rid of them in your heart. Get rid of them in your association with Me, so that I may use you to touch others. I require you to walk in integrity with a steadfast heart. Come to Me in repentance as you see any sign of these attitudes in your life. I will gladly remove them from you. They must be out of your life before we go on."
Joshua 7:13 AMP
Up, sanctify (set apart for a holy purpose) the people, and say, Sanctify yourselves for tomorrow; for thus says the Lord, the God of Israel: There are accursed things in the midst of you, O Israel. You can not stand before your enemies until you take away from among you the things devoted [to destruction].
Jeremiah 15:19 AMP
Therefore thus says the Lord [to Jeremiah]: If you return [and give up this mistaken tone of distrust and despair], then I will give you again a settled place of quiet and safety, and you will be My minister; and if you separate the precious from the vile [cleansing your own heart from unworthy and unwarranted suspicions concerning God's faithfulness], you shall be My mouthpiece...
Col. 3:9-10 AMP
9) Do not lie to one another, for you have stripped off the old (unregenerate) self with its evil practices.
10) And have clothed yourselves with the new [spiritual self], which is [ever in the process of being] renewed and remolded into [fuller and more perfect knowledge upon] knowledge after the image (the likeness) of Him Who created it.
A fool says in his heart that there is no God. Any degree of foolishness that is within us decreases our ability to see our Father for who He really is. The more foolishness there is, the less we appreciate the magnificence of God.
A lie is as deadly as murder to any life in Christ. Satan is the father of lies.
So, let's see...we lie to one another and harbor foolishness in our hearts by looking to the world for truth and comfort. Not a real good testimony.