If one watches whence the notion ‘I’ arises, the mind gets absorbed there; that is tapas. When a mantra is repeated, if one watches whence that mantr… - Ramana Maharshi

The spark of spiritual knowledge (jnana) will consume all creation. Since all the countless worlds are built upon the weak or non-existent foundation of the ego, they all disintegrate when the atom-bomb of knowledge falls on them.

Ishta-devata and Guru are aids - very powerful aids on this path. But an aid to be effective requires your effort also. Your effort is a sine qua non. It is you who should see the sun. Can spectacles and the sun see for you? You yourself have to see your true nature. Not much aid is required for doing it!

Unless one is happy, one cannot bestow happiness on others.