Matsya Purana 249.2

249.2

kathaṃ devā gatāḥ pūrvamamaratvaṃ vicakṣaṇāḥ.
tapasā karmaṇā vāpi prasādātkasya tejasā .. 249.2 ..

The Ṛiṣis asked:—We do not feel amply satisfied by listening to the glory of Nârâyaṇa that you have been pleased to relate to us We feel keen to hear more and more about it Pray tell us how the Devas became inmorta. What karmas they did, what tapasya they practised, or whose favor they gained, or whose energy they imbibed, that they obtained immortality in ancient days?—1-2