From Tripura Tapini Upanishad
?The syllable tat of the great mantra is the eternal Brahman, the supreme Lord, indefinable, impeccable, unconditioned, and unconstrained. He thinks, perceives, evolves, desires the status of consciousness. Thus that sole Deity, essentially good, evolves as the visible world. In the ascetics, sacrifices, mystics, He desires and what is desired is born. Being free from desires (in truth) and impeccable, He holds sway…?
This verse provides some interesting definitions of Brahman. There are two sets of characteristics. First Set:
[ul]
[li]?indefinable, impeccable, unconditioned, and unconstrained.? This is the nirguna aspect (purusa).
[/li][li]?He thinks, perceives, evolves, desires the status of consciousness.? This is the saguna aspect (prakriti). Note that it is through this aspect that the deity evolves as the visible world.
[/li][/ul]
Second set :
[ul]
[li]?He desires and what is desired is born.? This is the saguna aspect (prakriti).
[/li][li]?Being free from desires (in truth) and impeccable, He holds sway.? This is nirguna, purusa.
[/li][/ul]