Impersonalism can cause even the greatest to fall back to the material world
Brahma and the great rsis and the great master of yoga (Siva) are not ordinary
living entities; they are very powerful and have all the perfections of
mystic yoga. But still they have an inclination to try to become one with
the Supreme, and therefore they have to come back. In the Srimad Bhagavatam
it is accepted that as long as one thinks that he is equal
with the Supreme Personality of Godhead, he is not completely purified or
knowledgeable. In spite of going up to the first purusa-avatara, Maha-
Visnu, after the dissolution of this material creation, such
personalities again fall down or come back to the material creation.
It is a great falldown on the part of the impersonalists to think that
the Supreme Lord appears within a material body and that one should
therefore not meditate upon the form of the Supreme but should meditate
instead on the formless. For this particular mistake, even the great
mystic yogis or great stalwart transcendentalists also come back again
when there is creation.