Buddhist-Meditation-Systematic-and-Practical

Fourth, always maintain a natural mind; no force is
needed.
These four are very hard to keep without a realization of
the Dharmakaya. In mahamudra they are explained in
this way, but their correspondences with vajra-love are
never mentioned.
e. The act of vajra-love. These sections correspond with
the four mahamudra precepts given above.
First, if the semen is lost during the act of vajra-love one
should meditate upon its non-reality. If great pleasure
results from the act, then this pleasure must be identified
with non-reality.
"The meditations in this section are all within the
third initiation, but this process belongs to the
fourth, as we shall see. How can a meditator be
expected to keep this precept? Retaining the semen
during the sunyata meditation may lead on to the
practice of the fourth initiation; if it is lost, the
precept is not in this case broken, though the
practice is not good."
Second, hold the semen in the organ. To do this, one
must maintain a samapatti upon the vastness of the sky.
If one can do this, the meditator will avoid seminal
discharge from the reproductive organs. The samapatti
under these conditions will cause the semen to dissolve.
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