"Verily I say unto you, Among them that are born of women there hath not risen a greater than John the Baptist: notwithstanding he that is least in the kingdom of heaven is greater than he."
Why was the least in the kingdom of heaven greater than John the Baptist?
Roy used to say that because John knew Jesus to the Promised One (Matt 3: 13-17) and then doubted, sending messengers to ask (Matt 11: 2-3), he was less than the least. For nothing shall be impossible unto him who has faith even as a mustard seed (Matt 17: 20) and yet John did not leave place for the seed. (Matt 13: 3-9)
Nicole, however, said that a question is no sin, for it is written "Ask and ye shall receive" but rather, that the spirituality of John, though greater even than that of a prophet (Matt 11: 9), could not compare to the glory of the least in the celestial kingdom, who will inherit the fulness of God.
While I said, sometimes "the kingdom is heaven " refers to the celestial kingdom, sometimes it refers to the promised earthly kingdom to be born out of the church (JST Rev 12: 1-17), and sometimes it refers to the church when on earth in its fulness. John, though individually great and heir to the Aaronic Priesthood, was blessed with less than the least recipient of the collective blessings of the Church when led by the greater blessing of the Melchizedek Priesthood.