An offer of a sign as “deep as Sheol or high as heaven” (Isa. 7:11, NRSV) did not move Ahaz. So, when God says He Himself will come up with a sign (Isa. 7:14), we expect it to have breathtaking dimensions that only the divine imagination could devise (compare Isa. 55:9; 1 Cor. 2:9).
 Surprise! The sign is a son. But how could a young woman’s bearing a child and calling him “Immanuel” be a sign of biblical proportions?
 Who is the woman, and who is her Child?
 Nowhere does the Old Testament point out a fulfillment of this important sign, as it had done for the signs given to other people, such as Gideon (Judg. 6:36-40). So, here are some of the possible fulfillments, based on the Old Testament alone:
 Because the word for “young woman” refers to a young woman of marriageable age, many assume she is a married woman living in Jerusalem, perhaps the wife of Isaiah. Isaiah 8:3 does record the birth of a son to Isaiah by “the prophetess” (referring to his wife, whose prophetic messages consisted, at least, of her children; compare Isa. 7:3; Isa. 8:18). However, this son was named Maher-shalal-hash-baz (Isa. 8:1-4), not Immanuel. Nevertheless, the signs of the two boys are similar in that before they reach the early stage at which they can choose good or evil, Syria and northern Israel would be devastated (Isa. 7:16, Isa. 8:4).
 Some suggest that Immanuel is Hezekiah, son of Ahaz, who became the next king. But nowhere is the name Immanuel applied to him.
 Because Immanuel is somewhat mysterious and his name, commonly translated “God with us” refers to God’s presence, He could be the same as the special Son prophesied in Isaiah 9 and 11. If so, His exalted description as divine (Isa. 9:6) and “the root of Jesse” (Isa. 11:10, NRSV) surpasses anything that could be ascribed even to good King Hezekiah.
 A natural birth to an unmarried woman of marriageable age would result in an illegitimate child through illegal promiscuity (see Deut. 22:20, 21). Why would God refer to such a child as a sign to inspire faith?
 In contrast, the New Testament identifies Jesus as Immanuel (Matt. 1:21-23), born miraculously and with purity to an unmarried but betrothed virgin. Jesus is also the divine Son (Isa. 9:6; Matt. 3:17) and the “shoot” and “root” of Jesse (Isa. 11:1, 10; Rev. 22:16). Perhaps an earlier “Immanuel,” whose development proved to Ahaz the timeliness of prophetic fulfillments, served as a forerunner of Christ. We do not know. But we know what we need to know: “when the fullness of time had come, God sent his Son, born of a woman” (Gal. 4:4, NRSV), to give us the presence of God with us.