If John was born of priestly parentage (Luke 1.5), he must have abandoned the priesthood and taken up an ascetic mode of life in the Judean wilderness, where he subsisted on locusts and wild honey (Mark 1.6). Those who came out to him encountered a man dressed in camel‐hair homespun with a leather belt around his waist, the explicit garb of a prophet (2 Kings 1.8; Zech. 13.4). With prophetic zeal he preached a new message and offered a new rite. The message was that lineal descent from Abraham would not guarantee salvation. Abraham's merits would not suffice, but only an act of repentance that included the renunciation of all presumptions based on election or ethnicity (Matt. 3.9). The God that had called Israel out of Egypt and led it across the Jordan River was now creating a new people by passing them through the waters of baptism in that same river. The twelve stones that had been set up to mark Israel's crossing of the parted Jordan (Josh. 4) john the baptistwould themselves be raised up into twelve new tribes if the people of Israel would not repent. John was not founding a new religion but attacking the use of all religiousness as a defense against the demand of God for authenticity and justice.
This message of radical repentance was enacted in a rite of immersion in which the sin of presumption and the whole of one's old life were washed away. Those who rose out of the waters were as newborn infants (John 3.3–8), or as those who had passed from death to life, having been buried and raised from the dead (Rom. 6.1–11). These later Christian interpretations seem to have carried forward at least Jesus' own understanding of what John was about, for he spoke of his own baptism not as an event in the past but as a metaphor for his own approaching death (Mark 10.38–39; Luke 12.50).
John himself may have shared the idea, common in that period, that the last judgment would be enacted by a river of fire through which everyone would have to walk. In anticipation of that imminent judgment, John was inviting one and all to submit to God's judgment now, and by undergoing baptism to cleanse themselves of sin now, in advance of that terrible day. Those who had surrendered themselves to this washing would be preserved through the coming tribulation. They would be wheat gathered into God's granary, while the rest would be chaff burned in unquenchable fire (Matt. 3.12 par.).
John's message fell on Israel like fire on stubble. The Gospels report that “all” went out to hear him (Mark 1.5; Matt. 3.5; Mark 11.32 par.; Luke 7.29; Acts 13.24), and Josephus comments that he was highly regarded by the whole Jewish people (Ant. 18.5.116–119). The crowds that attended him included tax collectors and prostitutes (Matt. 21.32; Luke 3.12; 7.29). This simple act of immersion, unlike circumcision, made salvation accessible even to women. It was John, not Jesus, who opened a way to God for those who before had felt themselves excluded. And by his dress and diet, even by the metaphors he chose (a tree cutter, a thresher), John identified himself, and the one whom he awaited, with the lowly.
Judaism had never encountered anything quite like this, yet virtually everything recorded of John had parallels in Isaiah. These parallels include the following: an eschatological outpouring of the Holy Spirit (Isa. 32.15; Mark 1.8 par.) associated with the wilderness (Isa. 35.1–10; 40.3; 41.18–19; 43.19–20; Mark 1.3, 8, 10 par.); a spirit‐endowed one to come who will act as judge (Isa. 11.2–5; 42.1–4; 61.1; Mark 1.7–8 par.); Israelites as children of Abraham (Isa. 29.22; 41.8; 51.2; 63.16; Matt. 3.9 par.); unfaithful Israel portrayed as a brood of vipers (Isa. 59.5; 1.4; Matt. 3.7 par.) or as trees that God will hew down with an axe (Isa. 6.13; 10.15–19, 33–34; 14.8; Matt. 3.10 par.); wind/breath/spirit (Hebr. rûaḥ), and fire compared to a river in which one is immersed (Isa. 30.27–28, 33; 43.2; Matt. 3.12 par.); Israel as the threshed and winnowed one (Isa. 21.10; Matt. 3.12 par.); Israel washed clean (Isa. 1.16; 4.4; 52.11; Mark 1.4 par.); and works of righteousness mandated subsequent to washing (Isa. 1.16–17; Matt. 3.8 par.; Luke 3.10–14).
Despite such extensive parallels, John burst on the scene as a virtual mutant, for his rite of baptism, though outwardly similar to Temple lustrations, was wholly without precedent in its meaning. Nowhere in any Jewish source is rebirth made a metaphor for redemption. One is born a Jew. Proselytes might be “reborn” as Jews, but proselyte baptism was not practiced in the first century CE, applied only to non‐Jews, lacked an eschatological setting, and did not require running water. John's rite was so unique that he was named by it (“the Baptizer”), and Jesus clearly regards it as given to John by revelation from God (Mark 11.27–33). It circumvented the Temple and its rites; perhaps John's rejection of the priesthood is related to widespread revulsion against the corruption of the Temple and its priesthood in the first century CE.
John's presence in the wilderness has suggested to some that he might have at one time belonged to the community at Qumran, possibly even being raised by them as an orphan (Luke 1.80; his parents were elderly at his birth [Luke 1.7]). Both John and the settlers at Qumran glowed with eschatological fervor, expecting an imminent judgment and preparing for it in the wilderness. Both called on all Israel to repent, denying that mere Jewishness could save. Both used washings, broke with the Temple cultus, taught prayer and fasting, and focused on Isaiah as their guide to the future. But these qualities seem to have been shared by other sectarians who had located in the wilderness. The Jerusalem Talmud indicates that twenty‐four such distinct sects had come into existence by 70 CE (Sanh. 29c). And much of what John and Qumran held in common derives from Isaiah.
In key respects, moreover, John was quite different from the community at Qumran. They wore white linen; he dressed like the poor, in homespun. His disciples did not settle a community but wandered about with him. John required no three‐year period of probation but accepted whoever came, and they returned home rather than remaining with him in the wilderness. He was prophetic, public, missionary, inclusive; Qumran was exclusive, secretive, and withdrawn. His opening of salvation to prostitutes, tax collectors, and sinners must have scandalized that sacerdotal sect. Qumran's ethic applied only to its own community; John's was addressed to the entire nation, even the king (Mark 6.18). He called not for the communal sharing of goods but for sharing with the wretched who had nothing (Luke 3.11). Instead of demanding that his hearers abandon lives of moral ambiguity and move to the desert, John offered an ideal attainable in society by people unable to abandon everything (Luke 3.12–14). John's baptism, unlike Qumran's washings, was not daily, but once for all, and was not intended to achieve levitical purity, but to secure the forgiveness of sins in anticipation of the coming day of wrath. Even their common use of Isaiah 40.3 was different. Qumran interpreted it to mean that the preparation for the Lord's way was to be done in the wilderness by moving there and studying scripture. John seems to have understood the wilderness only as the place where the voice cries out. And Qumran expected a prophet, a messiah of Aaron, and a messiah of Israel; John expected only a coming judge different from all three.
The evangelists each employ the traditions about John in the service of the proclamation of Jesus. Each handles him differently, but all see him as the one who stands at the beginning of the gospel story, demanding of the hearer a beginner's mind and the jettisoning of all previous securities, so that a new word can be heard.