The generative fire that ordinarily spends itself outward can instead be withheld and turned back up the body to feed the higher birth. 3 conditions of that fire stand side by side: some hold it cold by nature, some are cut off by force, and some by their own choosing draw the seed of life upward, refusing its outward flow so its heat rises to open the kingdom within.
Only the third is the awakened act, the deliberate gathering of the creative power inward rather than a loss of it. What is not poured out below climbs, and that raised energy quickens the inner heaven in a person.
Eunuch: the generative or sexual energy withheld from outward use, held celibate so its fire can rise inward instead of being spent
Kingdom of heaven: the higher state within the body, the risen centers of the head that the raised creative force wakes and feeds