The special importance of the Ādi Granth as the defining scripture of the Sikhs has encouraged the production of commentaries whose language and approach reflect changing understandings of the Gurus' teachings over the last four centuries. The oral style of the earlier commentaries which typically demonstrate a catholic inclusiveness towards the wider Indic tradition came largely to be replaced in the twentieth century by the more exclusive approach of Sikh reformist commentators, in part aroused by the dismissive attitudes of the first English translation by Trumpp. Continuing to shape most modern understandings of the scripture, these highly organized commentaries composed in the new idiom of Modern Standard Panjabi are only now beginning to be challenged by new styles of exegesis being pioneered in the Sikh diaspora.