Buddhist-Meditation-Systematic-and-Practical

The navel-wheel may help one to acquire the
supernatural power of the knowledge of past lives of
oneself and others, and also to attain Nirmanakaya.
The wheel located in the abdomen can give rise to the
supernatural power of a magic body, as well as enabling
the meditator to practice vajra-love, leading to
possession of the mahasukhaprajnakaya.
c. The Wisdom-drops. The ancients classified "drops"
into four kinds: material-drops, breath-drops,
incantation-drops, and wisdom-drops. Material-drops
are the sperm or ova of the human body; breath-drops
are energies; incantation-drops are bijas and true words.
These latter two pertain to the lower three Tantras. It is
important not to mistake the wisdom-drops, which
belong to the anuttarayoga, for the sperm. Certain
ancient authors did this.
Many famous Tibetan works state that all the organs
(such as the heart, liver, stomach, etc.) are formed for
the material-drops; however, the drops and the organs
differ in their degree of purity. In my opinion, all the
organs belong only to the physical body and should be
treated as impure, as the Hinayana teachings indicate.
Of the four kinds, the Buddha-body has only the
wisdom-drops, included in practice of the anuttarayoga
in the second and third initiations. At the bottom of the
median channel are situated the red wisdom-drops,
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