“Rama, the incarnation of Vishnu, committed suicide. His ‘arse’ turned to moon ..” Why…

"Rama, the incarnation of Vishnu, committed suicide.
His 'arse' turned to moon .."

Why this blatant insult of Bhagwan Ram in @OfficialIGNOU book on 'Understanding Poetry' by Arun Kolatkar?

Are there similar poems on revered figures of other faiths in book?

Source @shashank_ssj