The formless and omnipotent God can easily assume form for the sake of devotees. An ordinary individual may not develop love as easily for the formless aspect of God (Brahman), as he/she would, if worshiped with form. So the need for idol worship.
We should worship him seeing all forms as different aspects of the same God….See Brahman in everything and everyone. Whomsoever you see, remember god’s form. Then everything will rise up from within. When our mind becomes expansive, we can merge with the infinite.
(Source an interview in Times
Aug 18, 2000 )