Dear  Mr Das,
I  already  read  the Sankarabhasya  on the Isavasyopanisad  and its English translation by swami Gambhirananda   [Ramakrisna  Mission].My problem is  that what the  following mantra means :
Andham tamah  pravisanti ye  asambhutim upasate.
Tato  bhuya  iva  te tamoya u sambhutyam  ratah //ISA-12//
Swami ji  translates  the view  of Sankara and writes :
Those who worship the unmanifested(prakriti) enter into blinding  darkness;  but  those who are devoted to the manifested (hiranyagarbha)  enter into  greater darkness.
Here the problem  arises  :
1,what is the import of  the worship of asambhuti-avyakrita [ unmanifest]  prakriti   and  sambhuti-     karyabrahma[ hiranyagarbha ].Hiranyagarbha is mentioned in hiranygarbha Sukta  too where it means  a huge form   of paramatma as 
Hiranyagarbhah samavartataagre bhutasya jaatah patir eka aasit.
.In  this way  hiranyagarbha  has two   meanings. what    import should be taken here as authentic?.
2.what is the system of said worships  of  avyakrita prakriti and  sambhuti ?
In haste I could not use diacritics.
Regards,
Girish K. Jha
Professor
Dept of Sanskrit
Patna University
Patna 800 005