Gita preaches real equality of all mankind and not just merely fraternity of all hindus. See also the experience of Adi Shankara whose disciples shouted to Nishada (lower caste) to make way. But Nishada(Lord Shiva in disguise) responded taht the same self resides in both, so how I can move away from self?
In contrast, see Prophet Muhammad's speech which only says that muslims r brothers of each other and all muslims constitute one brotherhood. Google and read his speech.
