How can I test whether a doctrine is true?

Les explains that to test whether a doctrine is true, you must examine every verse in its context and see if it dovetails with the whole of Scripture. He has told people over his twenty-some years of teaching that if a doctrine does not fit from Genesis 1:1 to Revelation 22, the last verse, you are on thin ice, because all Scripture will beautifully fit together if you understand it correctly. This principle applies to every passage, including difficult ones. For instance, in Revelation, a 'beast' is not a ferocious animal but a governmental power, and that understanding must fit the whole.