Christian Beware!!

Are you aware of the cunning devices that the enemy uses to cause us to doubt and lose assurance of our salvation?
What if I keep sinning then am I really a Christian? What if I don't have assurance every moment of the day or have joy every second? What if I seem to battle against these things does that mean I am not a Christian? John shows us that the enemy is so cunning that he uses truth to cause us to doubt! But we must not be unaware of his devices and must beware!