There is a distinct difference between truth and lies...as much difference as between light and dark, though not necessarily as easily perceived. The truth can never be a lie and a lie can never be the truth, nor is there such a thing as a half-truth. A half-truth is a whole lie, and, though men may use the Word of Truth to seek to promote their lies, the Word of God stands true. I have not written unto you because ye know not the truth, but because ye know it, and that no lie is of the truth (1 John 2:21).
Absolute truth can never come from an unregenerate heart any more than clean water can flow from a salty fountain. A lie may seem close to the truth, but in reality, it is a dangerous and subtle perversion that stems from Satan, the fahter of lies. False preachers take the pure truth of God's Word and seek to color it gray.
The spirit of error cries, "Christ loves everyone!" Scripture declares, "Esau have I hated." The spirit of error cries, "Christ died for everyone!" Scripture declares, "Christ died to save His people from their sins." (Matthew 1:21) The spirit of error cries, "Jesus wants to save you if you will let him!" Scripture declares, "Thou has given Him power over all flesh, that He should give eternal life to as many as Thou hast given Him." (John 17:2) The spirit of error cries, "We are saying the same thing, just in a different way!" Scipture declares, "Now I beseech you, brethren, by the name of our Lord Jesus Christ, that ye all speak the same thing, and that there be no divisions among you; but that ye be perfectly joined together in the same mind and in the same judgement." (1 Corinthians 1:10)
If the Spirit of truth is the one speaking, there can be no lie; and it will be the same truth spoken through all whom God sends. "For it is not ye that speak, but the Spirit of your Father which speaketh in you" (Matthew 10:20) A false prophet has no message but a lie, though they may use God's Word. "They change the truth of God into a lie; and worship and serve the creature more than the Creator, who is blessed forever." (Romans 1:25) The unlearned and unstable will always wrest the scriptures to their own destruction. (2 Peter 3:16)
He that knoweth God heareth us; he that is not of God heareth not us. Hereby know we the spirit of truth, and the spirit of error. (1 John 4:6)