Final answer:
The scripture in Isaiah does not directly mention John the Baptist, but it is believed to prophesy his role as the forerunner to Jesus. Christian gospels interpret Isaiah's words as referring to John, who baptized Jesus in the Jordan River, an act commemorated on January 6 by the Eastern Orthodox Church.
Step-by-step explanation:
The reference to John in the book of Isaiah often focuses on the prophecy that foretells the coming of a forerunner to the Messiah, who is understood by Christians to be John the Baptist. While Isaiah does not directly name John, the Gospel writers interpret Isaiah's prophecy as referring to him. The scene of Jesus' baptism by John in the Jordan River, which is mentioned in the New Testament and commemorated by the Eastern Orthodox Church on January 6, reflects John's significant role as the prophesied forerunner. During the baptism, the heavens open, and God's voice announces Jesus as His Son, while the Holy Spirit descends in the form of a dove. This event baptizes Christ amid representations of John's dire warnings and the personification of the Jordan River, drawing from both Christian texts and classical iconography.