The rising of consciousness through its stages either descends from the high heaven within or is manufactured by the reasoning of men, and the mind that only calculates cannot tell which. Baptism is the lifting of awareness up through level after level, and its source is questioned by the lower faculties that reason with themselves rather than rise. John carries the older current that prepares this ascent, and the question of whether that current is from the heaven within or merely of human making traps the mind that argues instead of ascends.
The reasoning powers of a person circle their own logic and cannot decide, because the source of the inner ascent is not settled by calculation; it is known only by the one who has actually risen through the stages.
Baptism: the rising of consciousness up through the stages of inner awareness
Heaven: the high inner realm, the elevated ground from which the ascent draws its source
John: the older preparing current within that makes way for the rising of consciousness