17, 18. How does Isaiah describe the empowering of Israel, and of what fulfillment may we be assured?

¹⁷ Jehovah continues to comfort his people: “Look! I have made you a threshing sledge, a new threshing instrument having double-edged teeth. You will tread down the mountains and crush them; and the hills you will make just like the chaff.

Isaiah 41:15,

¹⁸ Strength will be given to Israel to take the offensive and, in a spiritual sense, to subdue her mountainlike enemies. When Israel returns from exile, she will triumph over enemies who try to prevent the rebuilding of the temple and of Jerusalem’s walls. (Ezra 6:12; Nehemiah 6:16) However, Jehovah’s words will be fulfilled on a grand scale with “the Israel of God.” (Galatians 6:16) Jesus promises anointed Christians: “To him that conquers and observes my deeds down to the end I will give authority over the nations, and he shall shepherd the people with an iron rod so that they will be broken to pieces like clay vessels, the same as I have received from my Father.” (Revelation 2:26, 27) The time will certainly come when Christ’s brothers resurrected to heavenly glory will have a part in the destruction of Jehovah God’s enemies.​—2 Thessalonians 1:7, 8; Revelation 20:4, 6.