This the way: Read gods words daily and for long periods of tome and read it out loud to your self, as faith come by hearing and hearing by the word of God! and after you have been through the word front to back say at least five tmes, and more if you will, this will give some understanding as when you read out loud God will open the doors for you each time you go through,this will give you the ability by God to know when a preacher is preaching Gods word, as some preachers do not give the scripture all the time, and when you are read up you will know If what He is preaching is in line with Gods word or not, that is how you will know, that you know, that you know!