Similarity and difference between the two : Ch.up. Introduction-S.B.-yathaa advaitajnaanam manovr.ttimaatram ---------saamaanyam.
The similarity between non-dual realization and meditations is that both are mere modifications of the mind. svaabhaavikasya aatmani adhyaaropitasya --------------iti vis'eshaH.
The difference between the
two is this-non-dual realization removes totally the
cognition of all such differences as agent,
instrument, action and results, which are superimposed naturally
on the action- less Self, just as the appearance
of a snake
is superimposed on a rope.
This superimposition is
removed by the knowledge of the substratum. But
meditation consists in establishing a continuous
flow of similar modifications of
the mind with regard
to some object as prescribed by the scriptures, and
uninterrupted by any other
thought.