I will never forget it, it was about Prakriti and Purusha - the ‘ever-changing’ & the ‘changeless’. 

Essentially, there was only two things in the changeless, which was God (although, there were no attachments to a particular name, the rest of the class we came up with other potential words that would describe IT, and among them were Allah, The Eternal, The Creator, The Source, The Force, Mother Nature etc) AND the life of the human soul. Considering that in the Baha'i Writings it says that the human soul is on this earth to progress, I wanted to know what the reference of that aspect was in Yoga.