rudraditya vasavo ye ca sadhya
visve ’svinau marutas cosmapas ca
viksante tvam vismitas caiva sarve

"All the various manifestations of Lord Shiva, the Adityas, the Vasus, the Sadhyas, the Visvedevas, the two Asvis, the Maruts, the forefathers, the Gandharvas, the Yakshas, the Asuras and the perfected demigods are beholding You in wonder."

Sarve = all, vikshyanta = see, vismita = with wonder, tvam = You [Sri Krishna]. Everyone is viewing the Viswaroopam with wonder. Rudra = Rudras, aditya =Adityas, vasavo = Vasus [வசுக்கள் वसुनानी ], sadhya = Sadhyas. In Chapter 10 we have seen that some of these were mentioned. The Lord mentioned, there, that He was Shankara among Rudras, Vishnu among Adityas, etc. Now Arjuna is seeing the same. There he only listened to the Lord mentioning He was the Head among many groups. Though Arjuna believed what the Lord told, he had the doubt as how the Lord could be present simultaneously in Twelve Adityas, Eleven Rudras, etc. Besides, when the Lord mentioned that He was Shankara among Rudras or Vishnu among Adityas, we could not perceive that all of them were part of His divine body. But now we can see that everyone of them is a part of the Lord and all of them are supported by the Lord. Eleven Rudras, Twelve Adityas, Eight Vasus are mentioned. Visve sadhya means all the Nityasuris [நித்தியசூரி] in Vaikuntam. We should remember that excepting Sadhyas, who are in Vaikuntam, all others are in the Leela Vibhuti or Prakruti mandalam [as we are all]. Asvinau = Two Aswini devas, maruta = 49 Maruts [wind gods] [ Indra fractured the foetus in Diti's womb into Seven, and further fractured each of the Seven to another Seven, making 49 foetuses, by his vajra weapon]. Cosmapa = ancestors [the lecturer mentioned the word Ooshnata (could be a variance in the Gita edition), which means blood suckers - not the ghosts and spirits, we usually hear, as according to our sampradhayam, we do not believe in them and once we have surrendered to the Lord, nothing else would affect us. Here, it is to be interpreted as ancestors or pithrus [பித்ருக்கள்], like deceased parents, grand parents, and so on. Ooshnatha also means sucking atman. How can our deceased ancestors drink our atman? After all our ancestors were very much after our welfare. But when we perform the rites like tharpanam [தர்ப்பணம்] every amavasya or annual ceremony [திவசம்] on the particular thithi, in which they died, we offer pindam [பிண்டம் rice balls], sesama seeds [எள்] and water, they, in pithru form, drink them and so ooshnatha. Also it is said that a father's another form is his son. Thus we can say this atman shares the body of the children. Therfore, ooshnatha could mean drinking blood]. Gandarva = sky bound Gandarvas, yaksha =Yakshas, sura = Devas, siddha = accomplished persons, sangha = in groups. All these people see the Lord bewildered. The Lord's every action is fascinating, whether we hear about His Childhood pranks or His lifting Govardhana hillock. Naturally, Viswaroopam would be most astonishing to everyone. Another factor for their astonishment is that they see themselves in the Viswaroopam. Yakshas, Gandharvas, etc., are in their respective places, but they also see themselves in the Divine body of the Lord. This appears incredible to them and so astonished. in Upanishad - yatra poorve sadhya santi deva - sadhya means the residents of Vaikuntam, beyond Viraja river. Sadhya means those who had accomplished their ultimate desire [of reaching Vaikuntam]. Or, sadhyas could mean a separate division among devas.