[…] Our idea of God is gathered from all the attributes which I have enumerated.
Some say “God is simple, and whatever attribute you have reckoned as knowable are of His essence.”
When all these high attributes have been enumerated, are they all names of one essence?
[…] The energies are various, and the essence simple, but we say that we know our God from His energies, but do not undertake to approach near to His essence.
His energies come down to us, but His essence remains beyond our reach.
[…] 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. 11:6).
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.
“No man hath seen God at any time, the Only-begotten which is in the bosom hath declared him” (John 1:18).
What of the Father did the Only-begotten Son declare? His essence or His power? If His power, we know so much as He declared to us. If His essence, tell me where He said that His essence was the being unbegotten?
When did Abraham worship? Was it not when he believed? And when did he believe? Was it not when he was called? Where in this place is there any testimony in Scripture to Abraham’s comprehending?
When did the disciples worship Him? Was it not when they saw creation subject to Him? It was from the obedience of sea and winds to Him that they recognised His Godhead.
Therefore the knowledge came from the energies, and the worship from the knowledge. “Believest thou that I am able to do this?” “I believe, Lord” (Matt. 9:28), and he worshipped Him.
So worship follows faith, and faith is confirmed by power. But if you say that the believer also knows, he knows from what he believes; and vice versa he believes from what he knows. We know God from His power. We, therefore, believe in Him who is known, and we worship Him who is believed in.
Basil the Great (330-379): Letter 234 [slightly adapted].