Every reported revelation of his survives only as quotation inside the writings of the tradition that defeated him, presented in order to be ridiculed, and no manuscript, inscription or non-Muslim notice offers a control. This is a gap rather than a dispute: no scholar holds a position on the content of his teaching, because there is nothing independent to hold a position about.
What would resolve this A documentary or epigraphic find from al-Yamama independent of the Islamic historiographical tradition, or an early non-Muslim notice of the Hanifa movement of the 630s.
OpenArabian epigraphy and early Islamic historiographyP. Bearman, Th. Bianquis, C. E. Bosworth, E. van Donzel and W. P. Heinrichs (eds.), The Encyclopaedia of Islam, 2nd edition