The first and last word of this sádhaná also is total surrender. To the unit mind Brahma is unthinkable.

Acintyamavyaktamanantarúpaḿ shivaḿ prashántamamrtaḿ brahmayonim
Tathádimadhyántavihiinamekaḿ vibhuḿ cidánandamarúpamadbútam.

He is unimaginable, for He is beyond the sphere of imagination. Not only is He unimaginable, He is also unmanifest because He is inapprehensible to the sense organs through sound, touch, form, taste, smell etc. Any object, having the above five qualities like sound, touch, etc., no matter how huge it is, is apprehensible by the sense organs. He is formless, as we cannot give a form to infinity. But then, is not this perceptible world His form? Yes, it is, but these countless forms of this observable world are but His psychic manifestations. Only unit entities are evolved in the sphere of His mind as the objects of the unit minds, whereas countless and endless, big and small, unit entities are being created and recreated in the imagination of Brahma, the possessor of the infinite mind. Apparently they are His “form” in this observable world. But none of these forms of His psychic flow – none of these bubbles that are originating, rising and bursting are the ultimate entities. They are all progressing through spatial, temporal and personal changes with a view to merging in that Supreme Bearing, the Nucleus of the Thought Cycle. That is why we none of these mundane manifestations of Brahma can be taken as permanent and held on to its as such. No matter how charming or captivating a form of His may be, one day it must take its leave from us, must disappear to some unseeable region in response to the beckoning call of time, leaving us behind to rue and wail in profuse tears. So none of His unit forms can give us any perennial peace or real, abiding happiness. That is why a sádhaka is taken aback at the sight of the infinite, manifest form of the Infinite Brahma, Shrii Rádhá said:

Askest thou, Sakhi [Friend], the experience mine
Describing that Love with the love of mine
Each moment bringeth a newer theme
All my life that Form have I seen
Yet eyes untired, insatiate, keen
Only ears doth hark His honeyed hymn
Still indelible the touch on my ears
Sweet nights passeth in pining tears
The uncanny game beyond my ken
For aeons in heart my heart have I kept
Yet longing heart is ever bereft
Trekked many a talent His essence-den
Could none describe that feel divine
Sayeth Vidyapati, that Love so fine
Not one in a million could ever explain.