[3] When St Mary's was damaged in The Blitz, he moved to Old Saint Paul's, Edinburgh to continue his training.

On his death, the writer Richard Holloway wrote of Watt that "he spent his life battling against the tide of intolerance".

[1] Watt received the American Giorgio Levi Della Vida Medal and won, as its first recipient, the British Society for Middle Eastern Studies award for outstanding scholarship.

[4] Martin Forward, a 21st-century non-Muslim Islamic scholar, states: His books have done much to emphasize the Prophet's commitment to social justice; Watt has described him as being like an Old Testament prophet, who came to restore fair dealing and belief in one God to the Arabs, for whom these were or had become irrelevant concepts.

"[7]Carole Hillenbrand, a professor of Islamic History at the University of Edinburgh, states:[2] He was not afraid to express rather radical theological opinions – controversial ones in some Christian ecclesiastical circles.

For him, Trinity represents three different "faces" of the one and the same God.According to Carole Hillenbrand "an enormously influential scholar in the field of Islamic studies and a much-revered name for many Muslims all over the world".

[10] French jurist Georges-Henri Bousquet has mocked Watt's book, Muhammad at Mecca, describing it as "A Marxist interpretation of the origins of Islam by an Episcopal clergyman.

"[11][12] Danish historian Patricia Crone took issue with Watt's approach of extracting "historical" information from mythical stories by simply excluding the miraculous elements.