ANSWER: John the Baptist, the son of Zacharias and Elizabeth, was Jesus' cousin through Mary (Luke 1:36).
His life was unusual, even from before his conception. While performing his priestly duties in the temple, Zacharias was visited by an angel who said Elizabeth would conceive and bear a son named John. When Zacharias expressed doubt because of his and Elizabeth's advanced age, the angel struck him dumb until the baby was named (Luke 1:5 - 13).
The custom, in those days, was to name a son after his father, or a near relative. Zacharias had little choice. He could either accept the name his relatives chose, and remain mute for the rest of his life, or name him as the angel said, and have his tongue untied. Even though John was an unusual name in the family, Zacharias wisely gave it to his son (Luke 1:59 - 64).
John's life would certainly be unique. He would be a Nazarite from birth and be filled with God's holy spirit even while he was in the womb (verse 15). And he would be a special prophet who would prepare the way for the Messiah (verse 76). As he grew into manhood he began to lived in the wilderness, away from the cities (Luke 1:80). His clothing was rough, and his diet was strict (Matthew 3:4; Mark 1:6).
Why did he choose to live with wild animals in the wilderness, rather than in the safety of the cities? It was not likely his choice, but as the holy spirit drove Jesus into the wilderness (Mark 1:12), the spirit likely sent him there as well. Luke 3:2 says much about this.
Annas and Caiaphas were the High Priests, and to become a priest in the temple John would have tutored under them. But God wanted him to have the pure teachings, so God's message came to him supernaturally, away from the temple priests' influence.
One commentator wrote, " . . . he was not brought up in the schools of the prophets, nor in the academies of the Jews, or at the feet of any of their Rabbins and doctors; that it might appear he was not taught and sent of men, but of God."
The Jamieson, Faucett, and Brown commentary agrees regarding John's unique education when it states " . . . free from rabbinical influences and alone with God, his spirit would be educated, like Moses in the desert, for his future high vocation."
Returning to Gill's notes we read, " . . . and that it might be clear he had no knowledge of, nor correspondence with Jesus, whose forerunner he was, and of whom he was to bear testimony."
If John had no knowledge of, nor correspondence with Jesus, it had to be through the holy spirit that he was able to assert that he was the lamb of God (John 1:29, 36). Later he spoke out against king Herod, warning him his marriage to his sister-in-law was unlawful (Mark 6:17 - 18). For this, he ended up in prison.
The Jews in the first century were expecting a Messiah who would free them from Roman control. Jesus' mission had nothing to do with gaining Judea's independence so, in prison, John had time to think and entertain a doubt or two. He began to hear about the works of Christ, and may have wondered why Christ did not deliver him.
John's unresolved doubts finally led him to send two of his disciples to ask a few questions (Matthew 11:1 - 3) of Jesus. The answer they took back with them was to-the-point.
". . . tell him what you hear and have seen for yourself, that the blind and lame and lepers and deaf are healed, the dead are raised up, and the poor hear the good news of God's kingdom. Happy is he who has no doubts about me." (Matthew 11:4 - 6)
All this was heard by the people who surrounded them. They must have had some doubts about John, since he sent emissaries to question Jesus. But Jesus had no such doubts.
Christ asked the crowd what they went out into the wilderness to see. Did they go to see a weak, spineless person shaken by every wind of doctrine? Or a man in soft clothing? If that is what they expected, they were mistaken. One has to wonder whether Jesus' next statement was a jab at Herod. He said, "Those who wear silks and satins are in kings' houses" (Matthew 11:7 - 8).
Realizing that some of the people went to see a prophet, Jesus removed any doubt they might have by stating John the Baptist was far more than the average prophet (Matthew 11:9). He was the one Malachi spoke about (Malachi 3:1) who would prepare the way for the Savior.