His commentaries on the ideas of Fansuri and al-Raniri are the first definitive ones on early Malay Sufis based on 16th- and 17th-century manuscripts. In fact he discovered and published his meticulous research on the oldest extant Malay manuscript, wherein among other important matters, he also solved the riddle of the correct arrangement of the Malay-Islamic cyclical calendar. He was also responsible for the formulation and conceptualisation of the role of the Malay language in nation building during debates with political leaders in 1968. This formulation and conceptualisation was one of the important factors that led to the consolidation of Malay as the national language of Malaysia. As the Dean of the Faculty of Arts, University of Malaya, he personally initiated its implementation and mobilised the Faculty and the student organisations toward the systematic implementation of Malay as an intellectual and academic language. In fact, al-Attas's writings in Malay on Islamic subjects are unique in their poetic prose, and serve as literary models for the Islamic-oriented scholars and writers of Malaysia. This marks the first time that modern Malay is used intellectually and philosophically, thereby creating a new style of language.