As we learned last week, Cyrus' birth and name was predicted by Isaiah nearly two centuries before his Empire arose (Isaiah 45:1-7). God knows exactly what is happening in earth and who each ruler is, as well as what they will do. His interference in the events on earth are usually kept secret from us, but every now and again he pulls back the veil and allows us a glimpse of his glory. Cyrus is one of those glimpses.
God chose to subdue nations before Cyrus. He chose to cause his enemies to be defeated (vs 1). He would open up the double protective doors and gates of other kingdoms on his behalf. God would crush mountains and make crooked paths straight, a symbol of the king's complete victory in battles. All of this was done though Cyrus did not know God (vs 4-5, 3).
There is nothing and no one who can thwart what God has decided to come to pass (Isaiah 45:6-7; Job 42:2; Isaiah chapter 40; Colossians 1:15-16).
