The prophet who saw the LORD on his throne and the Servant on the cross
Isaiah's book is the New Testament's most quoted prophet. The four Gospels, Acts, Romans, 1 Peter — every major strand of apostolic theology reaches back into Isaiah for the language Christ has fulfilled. The Christian church reads Isaiah as the prophetic book most directly addressed to itself.
The call narrative in chapter 6 is the most famous prophetic vision in the canon. Isaiah sees the LORD seated on a high throne in the temple, the train of his robe filling the sanctuary, seraphim flying above calling *holy, holy, holy is the LORD of hosts; the whole earth is full of his glory.* The threshold shakes. Smoke fills the house. Isaiah cries out that he is undone, a man of unclean lips among a people of unclean lips. A seraph brings a coal from the altar, touches his mouth, declares him purified. Then the LORD speaks: *whom shall I send? who will go for us?* Isaiah answers: *here am I, send me.* The Christian tradition has from the patristic period read the *holy, holy, holy* as the first scriptural disclosure of Trinitarian worship. The Gospel of John (12:41) names Isaiah as having seen Christ in this vision specifically.
The Immanuel prophecy is the verse Matthew's Gospel will not let go of. *Behold, the virgin shall conceive and bear a son, and shall call his name Immanuel.* (Isaiah 7:14) The original context — a sign to Ahaz about the deliverance of Judah from Syria and Ephraim — is preserved by the Christian reading even as the messianic register is also held. Matthew 1:23 reads the verse as fulfilled in Christ's incarnation. The verse and its reception are one of the longest-running interpretive arguments between Christian and Jewish readers, and the editorial position is to take both readings seriously without flattening either.
The four Servant Songs (Isaiah 42, 49, 50, and especially 52:13 – 53:12) are where Isaiah's Christology becomes impossible to read past. *He was despised and rejected by men, a man of sorrows, and acquainted with grief.* *He was pierced for our transgressions; he was crushed for our iniquities; upon him was the chastisement that brought us peace, and with his stripes we are healed.* *He was oppressed, and he was afflicted, yet he opened not his mouth; like a lamb that is led to the slaughter.* The fourth Servant Song reads as if it were a Gospel passion narrative written seven centuries before the events. The early church seized on it: Philip's catechesis of the Ethiopian eunuch in Acts 8 turns on Isaiah 53:7–8. Peter's first epistle quotes it as the framework for Christian suffering (1 Peter 2:21–25).
The Jewish tradition has read the Servant differently. The Servant in many rabbinical readings is Israel itself — the suffering nation called to redemptive vocation. The editorial position is to honor this reading as a genuine textual possibility, and to confess the Christian reading that holds Christ as the Israel-in-one-person who fulfills the vocation Israel was given. The two readings need not collide on whether the text means *anything* — they collide on whether what the text means has been finally enacted, and where.
The second half of Isaiah (chapters 40–66) is the deepest prophetic articulation of comfort the Hebrew Scriptures contain. *Comfort, comfort my people, says your God. Speak tenderly to Jerusalem.* (Isaiah 40:1–2) *Every valley shall be lifted up.* (40:4) *A voice cries: in the wilderness prepare the way of the LORD.* (40:3) All four Gospels open John the Baptist's ministry by quoting these verses. The new exodus Isaiah announces — return from Babylon for the original audience, return from sin-exile for the Christian audience — runs through the second Isaiah and is taken up into the Christian gospel almost verbatim.
Isaiah's vocation was, by the prophet's own description, to preach to a people who would not hear (Isaiah 6:9–10). The seed planted in his ministry would not bear fruit in his lifetime. The seed bears fruit seven centuries later, in a Galilean preacher who reads from Isaiah's scroll in the synagogue at Nazareth and says, *today this scripture has been fulfilled in your hearing* (Luke 4:21).
Related entries: Sinai (Horeb), Mary (Mother of Jesus), The Shema