Therefore the Lord himself will give you a sign: The virgin will be with child and will give birth to a son, and will call him Immanuel. Isaiah 7:14
Quoting from today's passage, the Gospel writer Matthew states the birth of Jesus as a matter of fact: "This is how the birth of Jesus the Messiah came about" (Matthew 1:18). But imagine explaining that you were "with child" absent the physical act. Imagine trying to explain the pregnancy to your fiancé. Joseph couldn't accept it. His plan for a quiet divorce was the act of a godly man with a broken heart. He would move on . . . she would have the baby alone. That was the plan until the angel came and explained the situation to Joseph.
Now zoom back 400 years ... keep zooming ... 600 years ... a little more ... 700 years! Here the prophet Isaiah gives the information that moves the virgin birth from "unbelievable" to "expected." When God makes a promise, it is going to come true. His Word stands firm. He never goes back on His Word.
Works that way today, doesn't it? The promises God makes will come to be. He never renegotiates. He never changes His mind. He never bases His promises on our actions. We may have to wait, but the waiting allows us to develop our trust. When God makes a promise, it is a matter of fact, even before it happens.
Father, I thank You for always being able to trust Your Word. Thank You for always bringing about Your promises. Help us to keep depending on You as we wait. In Jesus' name. Amen.