And I will give you the treasures of darkness, and hidden riches of secret places, that you may know that I, the LORD, who call you by your name, am the God of Israel.
Read Chapter 45
Basil the Great
To one who believes, a promise is given by God: “I will give you hidden treasures, unseen ones.” When we have been deemed worthy of knowledge face to face, we shall see also the depth in the storehouses of God. - "Homilies on the Psalms 15.5 (Psalm 32)"
Who is the person whose heart has never been made to burn, as the Scriptures have been opened, with the pure words of God that have been tried in a furnace; who has not, by a triple inscription of them on the breadth of his heart, attained the mind of Christ, or been admitted to the treasures that to most people remain hidden, secret and dark, to gaze on the riches therein and become able to enrich others, comparing spiritual things with spiritual. - "In Defense of His Flight to Pontus, Oration 2.96"
Then the word of God will precede us and first humble the powerful of our earth—that is, these same harmful passions that we wish to subdue and that claim dominion for themselves and a most cruel tyranny in our mortal body—and it will make them submit to our investigation and our exposure. And, breaking open the gates of ignorance and smashing the bolts of the vices that shut us out from true knowledge, it will lead us to our concealed secrets and, according to the apostle, it will, once we have been enlightened, reveal to us “the hidden things of darkness and make manifest the counsels of hearts.” - "Institutes 5.2.2"
“I will give you the treasures of darkness.” … This is the way [Isaiah] referred to hell. Even if it was hell, it still preserved the sacred souls and precious vessels, Abraham, Isaac and Jacob. This is why Isaiah called it a place of treasures, even if in darkness, because the Sun of justice had not yet penetrated there with its rays or with any message on the resurrection. - "Demonstration Against the Pagans 4.14–15"