Notice that God gives examples of things He does from behind the scenes that people are unaware He is doing. By this, He is revealing a principle. He is doing similar things all the time, and people are just as unaware today as the ancients. He is manipulating events to cause people to react. In these verses, God is speaking to Cyrus, who is totally unaware that God has made it possible for him to be in the position to carry out what God wants him to do. He also informs Cyrus that he will do this job for Jacob's benefit, in this case for the Jews living under the Persian Empire.
In addition, we discover in verse 6 that the Jews do not know this either. The time will come, however, when they will know that God worked these things for their benefit and His purpose, and they will give God glory as the one and only Almighty God. A small-scale fulfillment of this occurred under Ezra and Nehemiah, but the greater fulfillment will not take place until the Great White Throne Judgment. Isaiah 45 gives the impression He is actively working, but that we are aware of only a tiny portion of His activity even in our own lives. Yet, as His children, we should be intently looking for His hand in our affairs.
John W. Ritenbaugh
God's Sovereignty and the Church's Condition (Part One)