And I will give thee the treasures of darkness, and hidden riches of secret places, that thou mayest know that I, the LORD, which call thee by thy name, am the God of Israel.
I will give thee the treasures of darkness - i:e., hidden in subterranean places: a common Oriental practice. Sorcerers pretended to be able to show where such treasures were to be found; in opposition to their pretensions, God says, He will really give hidden treasures to Cyrus (Jeremiah 50:37; Jeremiah 51:13). Pliny, 'Natural History,' 30: 3, says that Cyrus obtained from the conquest of Asia 34,000 pounds weight of gold, besides golden vases, and 500,000 talents of silver, and the goblet of Semiramis, weighing 15 talents.
That thou mayest know that I the Lord - namely, not merely that He was "the God of Israel," but that He was Yahweh, the true God. Ezra 1:1-2, shows that the correspondence of the event with the prediction had the desired effect on Cyrus.
Which call (thee) by thy name - who so long before designate thee by name (Isaiah 43:1).
(Am) the God of Israel.