John the Baptist was an itinerant preacher active in the area of Jordan River in the early 1st century AD. He was also called John the Forerunner by Christians, John the Immerser in some Baptist Christian traditions, and Prophet Yahya in Islam. He is sometimes alternatively referred to as John the Baptizer. In the Bible in the 4 canonical Gospels of Matthew, Mark, Luke and John, John the Baptist is highly mentioned.

The Gospels share the same basic outline: Jesus begins his public ministry in conjunction with that of John the Baptist, calls disciples, teaches and heals and confronts the Pharisees, dies on the cross, and is raised from the dead. Each has its own distinctive understanding of Jesus and his divine role. There are scholars who have stated that these Gospels were probably written between AD 66 and 110.

Many descriptions of John the Baptist note, "He was a good man who admonished the Jews to practice abstinence of Pharisaic virtue, lead a life of righteousness toward one another, and piety (religious devotion) toward God." Men could then join him in the rite of baptism for, he said, "... baptism was acceptable to God if people would use it not simply for putting an end to sin or for cases of proselyte, but for the sanctification of the body after the soul had beforehand been thoroughly purified by righteousness." People flocked in crowds to him, being stirred by his addresses. King Herod Antipas came to fear John the Baptist and had him put to death.

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