Buddhist-Meditation-Systematic-and-Practical

After the Buddha's parinirvana, history again definitely
records that 450 years passed before Bhadanta
Asvaghosa revealed and established the Mahayana.
Still later, when the Mahayana was flourishing, the
Siddha Nagarjuna obtained the Vajrayana teachings
from the Iron Pagoda in South India, according to the
Chinese and Japanese tradition (see also App. I, Part
Two, B, 1). However, the Tibetans say that the heavens
opened and the Vajrayana scriptures then descended.
Even among them we find the old and new, with the
Kalachakra (Wheel of Time) teachings admittedly the
latest.
The sequence of teachings is shown in history and there
is no good reason for us to turn these matters to our own
advantage, this way or that. Our classification should
only show the unity of the whole tradition, making it
clear that the three yanas are aspects of the One Way.
Certainly, as a believer and practitioner of the
Three-in-one, I believe the Buddha preached the
Hinayana personally in his Nirmanakaya; the Vajrayana
in his Sambhogakaya; and some of the Mahayana
personally while alive on earth, while other Mahayana
scriptures were derived from his Dharmakaya through
his outflowing bodies (Nisyandakaya) as Asvaghosa and
Nagarjuna.
b. Inherent Nature of the Teachings
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