I. The Essence of Buddha-Nature
Tathagatagarbha simply is
that Buddha-essence which has come,
and having arrived, is not gone;
yet gone is previous spiritual ignorance.
For Tathagatagarbha is the Buddha womb,
Sugatagarbha simply is
incorruptible, uncreated, and indestructible;
yet, it is no-self, and is not a soul.
For Sugatagarbha is Buddha-Nature
II. Buddha-Nature in All Beings
Hidden by mental and behavioural negativities
in every single being,
even the worst of sentient beings,
is that timeless, and
inherently transcendental Buddha-essence.
Indeed, all of us have
within us Buddha-Nature,
but few of us are able to realize it.
III. Buddha-Nature and the Luminous Mind
Unstained is the Luminous Mind,
by nature brightly shining and pure
for it is originally and naturally pure.
Yet it is enveloped in the garments of worldliness,
and soiled with the dirt of
attachment, hatred, delusion
and false imagining.
That stillness of mind
uncovered by the calm insight
of breath meditation
develops too by mindful meditation
this purity of heart
to realize the Luminous Mind,
which sees the original edge of reality
known as Buddha-Nature.
"Garments of worldliness" refers to skandhas, dhatus and ayatanas, specifically:
the Five Aggregates: http://en.wikipedia.org/wiki/Skandha
the Eighteen Dhatus: http://en.wikipedia.org/wiki/Dhatu, and
the Twelve Ayatanas: http://en.wikipedia.org/wiki/Ayatana