John’s ministry was in the wilderness of Judea (Mark 1:4; cp. Matthew 3:1). The term wilderness (G2048; eremos) doesn’t have to mean a desert or an arid wasteland. After all, John did baptize in the Jordan river (Mark 1:5) and near “many waters” i.e. springs (John 3:23), south and east of Jerusalem. The Greek word (G2048) also refers to uninhabited pasture lands (cp. Luke 15:4). So, John began his ministry in the southern part of Judea near the Jordan river, just before it emptied into the Dead Sea.
He preached “the baptism of repentance for the remission of sins” (Mark 1:4). The KJV says “John did baptize in the wilderness…” while the NASB says “John the Baptist appeared in the wilderness…” The article is before the verb, baptizing, and is literally translated into something like “John, the baptizing” or “John, the (one who was) baptizing…” which is adequately expressed in the phrase: John the Baptist or John the Baptizer. The Greek word did (KJV) or appeared (NASB) is ginomai (G1096), is translated: “it came to pass” in Mark 1:9 (see also Matthew 7:28; 9:10; 11:1; Mark 2:15, 23 etc.). So, the verse should begin something like: “It came to pass, John the Baptist was in the wilderness and preached…”
It seems, therefore, that John’s ministry began in the wilderness and not somewhere else and retreated there. Indeed, Luke 3:2 tells us that the word of God came to John in the wilderness. Therefore, in order to get the full impact of what Mark has in mind, one might read verse-1 and then verse-4 immediately afterward: “The beginning of the Gospel of Jesus Christ, the Son of God… and John the Baptist came (or appeared) in the wilderness preaching…” In other words, the whole purpose of John’s ministry was wrapped up in a wilderness context. It is there where John first appears on the pages of history, and it is there where he heralds the coming of Christ. John isn’t simply preaching baptism, but is, rather, preaching the coming of Christ and that the Jews’ needed to change in order to prepare for their Lord. Baptism is a symbol that expressed a Jew’s prepared state of mind.
The Greek word Mark used for repentance is metanoia (G3341), and it simply means change, as though one reconsidered what one was doing; it is an afterthought. Mark uses the word only once more in his narrative at Mark 2:17, where Jesus says he didn’t come to call the righteous (to change) but the sinner to reconsider his way (relating to repentance). The idea is that in the beginning Israel was called into the wilderness to make a covenant with God, and they had to wash their clothes in order to prepare for that event (Exodus 19:10, 14). However, not only did Israel make a covenant with the Lord, but she also broke that covenant, and the Lord divorced her by casting her from his presence and sending his people into exile. While it was true that at least some of the Jews had returned to their homeland, they were still living out a broken covenant. God had not remarried them. They were yet divorced and in spiritual exile. John called them out into the wilderness to prepare themselves for a new covenant (cp. Jeremiah 31:31-34), and told them they needed to change (G3341) their lives, their behavior, their attitude toward God and sin. When they committed themselves to change, John baptized them “for the remission of sins,” or put another way, if they entered into a new covenant with the Lord, promising to change, he would enter into that new covenant with them and promised to forgive them and remember their sins no more (cp. Jeremiah 31:34; Ezekiel 36:25).
It would be a mistake to view John’s baptism as a Levitical cleansing (Leviticus 14:8-9; 15:5). Even pagans observed types of ceremonial cleansing in their religious practices. This is categorically not what John was doing. Whenever a gentile embraced the Jewish faith, he was baptized, making a once-and-for-all statement about his commitment to the God of Israel. The washings or baptisms that came later concerned other matters, but this first baptism was of singular importance and represented a change of direction and attitude toward life and God. It was this kind of thing that John’s baptism represented. John was telling the Jews they needed to be baptized to the Lord, like they demanded gentiles to be baptized to the Lord (cp. Isaiah 64:6). It made no difference that they were Jews (John 3:4) and descendants from Abraham (Matthew 3:9; Luke 3:8). They had been divorced by the Lord, and in their present condition it was as though they were gentiles to the Lord (Amos 9:7; cp. Isaiah 1:9-10); they had to be remarried, if they wanted to have any relationship at all with him (cp. Revelation 2:9; 3:9; John 8:39-40; Romans 2:28-29). In other words, although they were Jews by nature, they had come to be gentiles in the spirit, having no covenantal claim on their Lord’s mercy.