Impossible Prophecy Fulfilled

So when the apostle Matthew mentions a prophecy in Matthew 1:21-23, he is quoting from the prophet Isaiah written in 700BC (before Christ incarnate). Is that not mind blowing? The prophecy states in Isaiah 7:14, “Therefore the Lord himself will give you a sign. Behold, the virgin shall conceive and bear a son, and shall call his name Immanuel.”