Can you tell the difference between a bonded leather cover on a Bible and a genuine leather one? When you first see a brand new Bible, it may not be readily apparent which is bonded leather and which is the genuine one. But, the more you investigate (look at it close, open it, bend it, touch it, use it), you will find which one is genuine and which one is not.
Can you tell the difference between a truth and a lie? Can you tell the difference between a sound gospel preacher and a false teacher? Can you tell the difference between a doctrine that is Scriptural and one that is not? Paul said to “test all things” (1 Thess. 5:21). John said not to believe everything we hear but to “test…whether they are of God” (1 John 4:1). How do we put teachers and their teachings to the test? The same way the Bereans did—search the Scriptures to find out whether the things they say and teach are so (Acts 17:11). If you look close and test all you hear with the genuine Word of God, you will know the difference!