“Knowledge” has always held a pivotal place in Islam, but the nature of knowledge itself remains comparatively under-explored within Islamic scholarship. The aim of the present chapter is to bring together the key ideas of Professor Syed Ali Ashraf (1925–1998) on the concept of knowledge and then to provide a critical discussion of these ideas from a broadly western perspective. Professor Ashraf was an academic in the Sufi tradition, and the high respect in which his scholarship was held is evidenced by his roles as Director-General of the World Centre for Islamic Education in Jeddah, Founder of the Islamic Academy in Cambridge, and Vice Chancellor of Darul Ihsan University in Bangladesh. He has written little directly about the definition, sources, nature and classification of knowledge, but an examination of the epistemological assumptions that underpin his writing about education is very revealing in the insight it provides into the topic. The chapter is divided into two main sections. The first examines Professor Ashraf’s views on such issues as the pointlessness of pursuing knowledge for its own sake, the inferiority of knowledge acquired through human effort compared to knowledge originating from divine revelation, the need for the Islamization of knowledge, and the relationship between knowledge and education. His views are compared to those of Professor Syed al-Attas, and the dependence of both on al-Ghazali is acknowledged. The second section provides a critical discussion of these views from a positivist and rationalist perspective and draws attention to the gulf that exists between Islamic and western ways of thinking about the nature of knowledge. The conclusion highlights the difficulties encountered by Muslims, especially those living in the West who are faced with these conflicting and incompatible perspectives and explores ways of encouraging dialogue and mutual understanding in the future.