Came across this interesting article on Mantra & Spiritual evolution - Glad to share...
A Dev is the energy responsible for a particular phenomenon
of nature. As you progress in yogic practices (Sanatan Kriya), these energies
are revealed to you.
Not only do they exist but they actually interact with you
and aid your evolution process.
Evolution is moving to a dimension that is higher than your
current state. In the etheric world, it is moving from a grosser to a subtler
dimension. With relation to your etheric double, it is moving from your basic
chakra upwards. This upward movement happens through the etheric reflection of
your spinal cord called the sushumna nadi. We know that a strong and supple
spine is a prerequisite for yog.
Each of these Devas reside in the etheric portion relevant
to every vertebra. For instance, the tail bone in the spinal cord corresponds
to the location of mooladhar chakra and is the seat of Lord Ganesha, the energy
closest to the physical and of great importance in removing obstacles in the
physical world. Evolution too starts from the base of the spine upwards; hence,
one has to go to Lord Ganesha for blessings for the journey beyond.