"And if We willed, We could show them to you, and you would know them by their marks."—meaning: their description without having to be told. "But you will surely know them by the tone of their speech"—meaning: their pretexts and the falsehood they used as excuses during the expeditions and in what they said. Then Allah informed His Messenger about them; thus, after this verse, no hypocrite remained unknown to the Messenger of Allah, and the Prophet disclosed them to Hudhayfah.

Muhammad said: "(In the tone of their speech)" means: in the tone of their words and their meaning, and the root of the word