"Behold, the virgin shall be with child and shall bear a Son, and they shall call His name Immanuel," which translated means, "God with us." (Matthew 1:23 NASB)
"Only Christians believe in a God who says, 'Here I am alongside you. I have experienced the same suffering you have. I know what it is like.' No other religion even begins to offer that assurance." (Tim Keller, "Preaching Amid Pluralism," Leadership Magazine, Winter 2002, pp. 34-35.)
The fulfillment of Isaiah's prophecy happened in the birth of Jesus. But it was not simply in the birth of a child to Mary. The vital preface to that birth, found in announcements by angels to both Mary and Joseph, revealed an act of God that staggers the mind. This was no illicit conception of unwed parents. It was no ordinary conception of a married couple. It was a birth created by an act of the Holy Spirit, planting a child in a virgin's womb. But it's even more than that. If you ever wondered how Joseph handled the news that the young woman to whom he was engaged was pregnant, you might consider the words of the angel. "They shall call His name Immanuel." It's a name that means "God with us."
The incarnation is not totally explainable to us, for it is surely the most unique birth, of the most unique person, ever born. Consider the power of his miracles, the wisdom of his teaching, the magnetism of his person, the uncanny combination of strength, and love, and grace, and mercy. This is one of the most important things about the incarnation. Since Jesus was God in the flesh, he reveals God to us in the only way we can grasp the information. He is the divine, packaged in flesh, to help us see the invisible God with our eyes, our minds, and our senses. Only because God is "with us" in human form can we possibly fathom the unfathomable.
"God with us" helps us understand God's ultimate will. Through the virgin birth, God came in the realest sense. Because Jesus was divine in human form, his actions were God with us. His role as Savior is that of God acting on our behalf. With us means we are never alone. Next time you feel lonely and think that nobody cares, remember Jesus, who is God with us.