This word “prove” means to “examine” and is translated from a very common and familiar word to New Testament students. It means “test, approve, distinguish or judge.” This verse carries the idea of testing something in order to ascertain its true character or nature.
For example, it was used to describe the testing of metals or gemstones to determine their true value or quality.
Ancient stone masons would go through the quarry and examine rocks. On those stones that passed the examination was painted a delta or letter “d” for approved. Those stones that failed the inspection were labeled with an alpha or “a” for unapproved. So this verse means that we are to go through life inspecting everything to see what is true and what is false, what is good and what is evil, what is right and what it wrong.
Note closely that we are to “prove all things” or “examine everything”. We are not only to discern religious TV shows and preachers, but everything in life. We are to carefully examine what we do for entertainment. Do my activities fall to the side of good or evil? … wholesome or unwholesome? Would I feel comfortable if Jesus was right there with me? Are your political views tied to your understanding of Scripture or for party loyalty?
We know I Corinthians 10:31 says, “Whether therefore ye eat or drink or whatsoever ye do, do all to the glory of God.” Yet, if we are honest we often do many things to the glory of self. Examine your heart. Why are you doing what you are doing? What is your motivation?