Though Ahaz would not ask, the Lord gives a sign to the House of David — “the virgin shall conceive and bear a son, and shall call his name Immanuel” (Is. 7:14). With this promise, He signifies that salvation is by His grace alone. It is no work or achievement of man, but the Lord’s own work and His free gift. The promise is fulfilled as the Son of God is conceived and born of the Virgin Mary, and the sign is received in faith by the House of David in the person of Joseph (Matt. 1:20–24). “Incarnate by the Holy Spirit of the Virgin Mary” (Nicene Creed), God is with us (Immanuel) in the flesh of Jesus, Mary’s Son. Joseph believes that Word of God and so demonstrates a marvelous example in his immediate and quiet obedience, taking Mary to be his wife and caring for her in faith and love. He loves her because the love of God is manifest in this, that “the Father has sent his Son to be the Savior of the world,” to be “the propitiation for our sins” (1 John 4:10–14).