“Test all things; hold fast what is good“
By challenging the Thessalonians to not despise prophecies, Paul did not want to imply that they were to be gullible and swallow any religious nonsense that might come their way. This verse puts a qualification on the previous verse.
We test preaching (5:20) against the Word of God. The final arbiter of truth is God’s Word. The word “test” means to test with the purpose to approve. We approve prophecy by the Bible.
“To the law and to the testimony! If they do not speak according to this word, it is because there is no light in them” (Isaiah 8:20).
“Beloved, do not believe every spirit, but test the spirits, whether they are of God; because many false prophets have gone out into the world” (1 John 4:1 ).
Satan is in the business of imitating God’s Word. Christians are to test truth as a FBI agents examine counterfeit money. Some people will contrive ideas and pass them off as God’s ideas.
God wants us to test “all” things, not simply most things. Do not condemn anything without first investigating it. On the other hand, do not accept anything until you first test it against the objective truth of God’s Word.
It is difficult to put aside our preconceptions about truth because we build security around what we believe. Honesty means that we examine the Bible without bias as much is possible.
All Christians need to develop a sense of discernment.
Some people try to pawn off their personal ideas as being from God. This confuses the voice of God with the voice of man.
One drop of poison in your food spoils the entire meal. False doctrine usually carries much truth. The Devil is too smart to tempt you with absolute contradiction to what you believe. He takes what you believe and modifies it slightly. Peter, for example did not discern the plan of God, so Jesus rebuked him.
“But when He had turned around and looked at His disciples, He rebuked Peter, saying, ‘Get behind Me, Satan! For you are not mindful of the things of God, but the things of men’” (Mark 8:33).
Jesus said in effect, “Peter, you are peddling the Devil’s lie. What may look right to you is, in fact, a lie.” Very few Christians today take the time to sniff out error. Everything seems to sit right with them because they do not rightly divide the word of truth.
“Be diligent to present yourself approved to God, a worker who does not need to be ashamed, rightly dividing the word of truth” (2 Timothy 2:15 ).