Deuteronomy 33:17

¹⁷ His glory is like the firstling of his bullock, and his horns are like the horns of unicorns: with them he shall push the people together to the ends of the earth: and they are the ten thousands of Ephraim, and they are the thousands of Manasseh.

Treasures of darkness, and hidden riches of secret places

In Isaiah 45:3, this signifies interior intelligence and wisdom from heaven.