SrI vedAnta desika in his tatva-mukta-kalApa points out that the
pAncarAtra system originated from the ekAyana Sakha portion of
the veda-s. The chAndogya upanishad refers to the ekAyana Sakha
as the veda of veda-s, the treasure of the gods, and the sacred
utterance among all utterances. ekAyana means "the only means".
".....pancamam vedAnAm vedam pitryam rASim daivam nidhim
vAkovAkyam ekAyanam ....iti" (chAndogya XIII.6.1.1). The
mahAbhArata states that this ekAnti dharma was promulgated by
Lord nArAyaNa during the first stage of the cosmic evolution, or
the First Birth of brahma (mAnasa). The terms "bhAgavata"
doctrine and "sAttvata" doctrine, are also used synonymously
with the term "pAncarAtra". While elucidating the nature of the
ekAnti dharma, the Santi parva of the mahAbhArata
(332-16-8,336-1-76, 337-61-7) refers to the sAtvata, bhAgavata,
and pAncarAtra systems. This goes to show that all these are
closely connected systems which believe in the worship of one
God. The mahAbhArata states that the sAttva