Expositor's Bible Commentary Commentary John 1:27

"[even] he that cometh after me, the latchet of whose shoe I am not worthy to unloose." — John 1:27 (ASV)

John suggested that he did not profess to speak with ultimate authority. He was, after all, preaching repentance and was calling for baptism as a confession of repentance in expectation of the greater person who was yet to appear. It seems likely that John’s baptism followed the pattern of proselyte baptism, which required a renunciation of all evil, complete immersion in water, and then reclothing as a member of the holy community of law-keepers.

John drew his reference to untying the sandals of his successor from the practice of using the lowest slave of a household to remove the sandals and wash the feet of guests. John’s witness, therefore, reflected the exalted nature of Jesus and placed the latter far above himself.