Question: On what should one concentrate during Upasana?

Ans:

Those believing in Divinity 'with form' (Sakar) are advised to concentrate on an idol or picture of Gayatri , whereas those having faith in formless God (Nirakar) may concentrate in the central, part of the sun, all the while imagining that the ethereal solar energy is permeating and purifying the trio of, physical (Sthool) subtle (Sooksham) and causal (Karan) bodies of the Sadhak). During Upasana , it is necessary to concentrate one's thoughts exclusively on the deity. Persistent attempts should be made to restrain thoughts from wandering. Extraneous thoughts should not be allowed to enter the mind .