It's quite difficult to discern a false doctrine nowadays, Jesus told us in the book of Mathew chapter 24 in the 5th and the 11th verse that many will come in his name just to deceive people, he went on to speak about false prophets, that many will rise in the last days for the purpose of this evil seduction to deceive people with this jezebel doctrine, but in the 4th verse of that same chapter Jesus told us to take and not to deceived, if our master says so, then it's possible not to be deceived and will be alot easier not to be deceived if we use the word of God which is the Bible as our mirror, when we are a reflection of God's Word, the deception can't get to us.