2.  But, it is replied, if you are ignorant of the essence, you are ignorant of Himself.  Retort, If you say that you know His essence, you are ignorant of Himself.  A man who has been bitten by a mad dog, and sees a dog in a dish, does not really see any more than is seen by people in good health; he is to be pitied because he thinks he sees what he does not see.  Do not then admire him for his announcement, but pity him for his insanity.  Recognise that the voice is the voice of mockers, when they say, if you are ignorant of the essence of God, you worship what you do not know.  I do know that He exists; what His essence is, I look at as beyond intelligence.  How then am I saved?  Through faith.  It is faith sufficient to know that God exists, without knowing what He is; and “He is a rewarder of them that seek Him.” Heb. xi. 6.  So knowledge of the divine essence involves perception of His incomprehensibility, and the object of our worship is not that of which we comprehend the essence, but of which we comprehend that the essence exists.