3:1 Luke’s historical interest, evident from the outset of the Gospel (1:1–4), manifests itself again, as he plots the commencement of John’s preaching against the historical backdrop of the day. John begins to preach in the fifteenth year of Tiberius Caesar (r. AD 14–37). Pontius Pilate serves as the prefect of Judea from AD 26 to 36, and he plays a critical role at Jesus’ trial. It is no mistake, incidentally, for Luke to identify Pilate as a governor instead of a prefect. Luke is not writing technically about these matters. Herod Antipas, the son of Herod the Great (r. 37–4 BC), reigned over Galilee and Perea from 4 BC to 39 AD. Philip, another son of Herod the Great, ruled from 4 BC to AD 34 in the Transjordan, over Iturea and Trachonitis. We do not know much about Lysanias, who ruled in Abilene (and some have even argued that Luke makes a mistake here), but our evidence is partial, and there is some evidence for his reign.38 The date in which John begins his ministry is probably AD 26/27. By listing these rulers Luke indicates that the ministry of the Baptist (and by implication that of Jesus) impacts the entire world.

3:2 John’s ministry commences while Annas and Caiaphas are high priests. Technically, Annas serves as high priest from AD 6 to 15, with Caiaphas serving from AD 18 to 36. Luke is likely featuring the collaboration of Annas and Caiaphas, for Annas is hugely influential over the high priesthood in Israel for years. For instance, Caiaphas is Annas’s son-in-law, and we see their collaboration in John 18:12–28. Five of Annas’s sons also serve as high priests. During the days of Annas and Caiaphas, probably in AD 26/27, the word of the Lord, the prophetic word, comes to John the Baptist. The word of the Lord has not been declared authoritatively since the days of Malachi. First Maccabees confirms this, for we are told that “the Jews and the priests were pleased that Simon would be their leader and high priest forever, until a trustworthy prophet should arise” (1 Macc. 14:41)). In the days of the Maccabees no inspired prophet spoke, and hence it was determined that Simon would be their leader and high priest in the meantime. Now in the days of John the word of God is again being spoken. John ministers in the wilderness, which symbolizes that the nation is in exile, that the covenant promises have not yet been realized.

3:3 John is located in the wilderness at the Jordan. In other words, he is on the other side of the Jordan, and his ministry is in the wilderness. Israel, which knows its own history, would not fail to catch the symbolism. The nation is at the same place it was when it wandered in the wilderness for forty years and when it was in exile for seventy years in Babylon. The new exodus that Isaiah regularly promises is still to be completed (cf. comment on 3:4). The nation must go through the Jordan again, so to speak, and thus they are baptized, that is, immersed, in the Jordan to symbolize their cleansing from sin. The new exodus Isaiah promised would lead to forgiveness of sin (cf. Isa. 40:2; 42:24; 43:24–25, 27; 44:22; 50:10; 53:10, 12; 58:1; 59:2, 12; 64:5). Such forgiveness would not be received without repentance. Israel must turn from its selfish way and give itself to God.

3:4–6 Luke indeed understands the Baptist’s ministry in terms of the new exodus promised in Isaiah, as confirmed by his citation of Isaiah 40:3–5. In Isaiah the wilderness represents the desert between Babylon and Israel, the path Israel will have to traverse in order to return home. The Baptist is the voice crying out, summoning Israel to prepare the Lord’s way. In the OT the Lord whose way is prepared is Yahweh, but here the Lord is Jesus.

The imagery of making paths straight, filling valleys, leveling hills and mountains, straightening the crooked, and smoothing out rough places refers to the topography Israel would traverse in returning from Babylon. At the same time, the imagery should be interpreted in terms of the new life demanded of Israel. Israel’s life must be straightened out; they must renounce their pride and sin. This is another way of saying that Israel must repent in order to see God’s salvation; Israel must return to the Lord to experience eschatological deliverance. The salvation and forgiveness proclaimed by John is found finally in Jesus himself (Luke 2:30; 19:10). Luke clearly draws on the LXX version of Isaiah, which adds “salvation,” but in the Lukan version the “glory of God” that appears to all is omitted (Isa. 40:5), perhaps because salvation is another way of speaking of God’s glory.