Yoga is definitely a very beneficial exercise. However the
purpose of yoga has disappeared in modern times. Indian yoga which
has a highly spiritual nature has degenerated into a form of
'mental and physical exercise'.
Pls see the hindu website: Modern Yoga versus Ancient
Yoga
The goal of Yoga is Yoga: The goal or
destination of Yoga is Yoga itself, union itself, of the little
self and the True Self, a process of awakening to the preexisting
union that is called Yoga. While it is not the intent of this
article to give a final or conclusive definition of the term
Yoga--which can be described in different ways--it has to do with
the realization through direct experience of the preexisting union
between Atman and Brahman, Jivatman and Paramatman, and Shiva and
Shakti, or the realization of Purusha standing alone as separate
from Prakriti. The mere fact that one might do a few stretches with
the physical body does not in itself mean that one is headed
towards that high union, referred to as Yoga.
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Perception has recently shifted: The typical
perception of Yoga has shifted a great deal in the past century,
particularly the past couple decades. Most of this is due to
changes made in the West, particularly in the United States, though
it is not solely an American phenomenon. (Similar shifts have
happened with Tantra as well.)
Gist of the two perspectives: The gist of the
shift can be summarized in two perspectives, one of which is modern
and false, and the other of which is ancient and true.
*
False: Yoga is a physical system with a spiritual component.
*
True: Yoga is a spiritual system with a physical component.
The false view spreads: Unfortunately, the view that Yoga is a
physical exercise program is the dominant viewpoint. The false view
then spreads through many institutions, classes, teachers, books,
magazines, and millions of students of modern Yoga, who have little
or no knowledge or interest in the spiritual goals of ancient,
authentic Yoga and Yoga Meditation.
pls read entire article in that website
Tibetan Buddhism yoga however, is fully for spiritual
purposes.