Shree Bhagavaan uvaacha:
sudurdarshamidam roopam drishtvaanasi yanmama |
devaa apyasya roopasya nityam darshanakaankshinaha || 52 ||

Shree Bhagavaan said:
It is extremely rare (for anyone) to see that form of mine that you have just seen. Even the gods eternally long to see this form.

sudurdarsham: extremely rare to see
idam : this
roopam : form
drishtvaan : seen
asi : you have
yat : that
mama : mine
devaaha : gods
api : even
asya : this
roopasya : form
nityam : eternally
darshanakaankshinaha : long to see
The Gita uses a lot of the Katha Upanishad for its teachings. In that Upanishad, the young boy Nachiketa approaches the lord of death Yama for spiritual instruction. His most powerful question to Yama is : what happens to the soul after death. Yama tries to distract Nachiketa with boons of wealth and power, but fails. Eventually he responds : “Nachikata, even the gods are even anxious to know the answer to this question, and have never been able to figure this out”.
The same language is used by Shri Krishna in this shloka. He says that the gods have desired to see Ishvara’s cosmic form since eternity, but have not been able to do so. It is “sudurdarsham”, extremely difficult and rare to see, it is next to impossible. They may have seen Lord Naarayana in his four-armed form, but not the universal cosmic vision seen by Arjuna. And they will probably not see it in their lifetime.
Why is it the case the the gods cannot see this vision? Let’s investigate the nature of gods. They may be more powerful than humans, but they are subject to the three gunaas like every other aspect of creation. Which means that they also are impelled by selfish desires. Even Indra, the king of the gods, starts plotting to remove anyone who has an eye on his throne. So what Shri Krishna means here is that humans, gods, demons, anyone who is part of this creation, will never get to see this cosmic form unless they have a specific quality. Shri Krishna will give a detailed answer to this question soon.