esa te ’bhihitah krtsno
devanam api durgamah
Thus have I related to you — both in brief and in detail — a complete survey of the science of the Absolute Truth. Even for the demigods, this science is very difficult to comprehend.
The word devanam indicates those living beings in the mode of goodness (such as demigods, saints and pious philosophers) who nevertheless cannot understand the Absolute Truth because they lack full surrender to the Personality of Godhead.