The Bible tells us in this verse that Jesus would be virgin-born. Later, in Isaiah 9:6, the Bible says, "For unto us a Child is born, unto us a Son is given." A child is born speaks of Jesus' humanity. A Son is given speaks of Jesus' deity.
Jesus left His throne in glory, stepped out of the ivory palaces, and came down into this world of woe. Our Lord came not in a jeweled chariot accompanied by angels but through the portals of a virgin's womb. There's no way that you can be saved apart from the virgin birth. It is fundamental. Jesus was born of a virgin so that He might be the God-man. Immanuel: God in human flesh, sent to Earth for us.
Isaiah 7:14; Matthew 1:22-23