Explanation of the author's statement and his saying: (And who is more truthful than Allah in speech) - (And who is more truthful than Allah in saying)

The Shaykh : Then the author (may Allah have mercy on him) moved on to the attribute of speech. He mentioned the verses regarding this. Speech is perfection, not deficiency. Speech is perfection, not deficiency. For this reason, they—meaning the Asha'irah—said that it is a necessary consequence of the perfection of Allah (Mighty and Majestic) that He is a Speaker. But, unfortunately, they interpreted speech as will be mentioned, if Allah wills, contrary to its true reality.
The author (may Allah have mercy on him) says:
is an interrogative noun meaning negation. Using the form of interrogation for negation is more emphatic than using a simple negation or its true form, because in that case, what is it?
The student: Implied

The Shaykh : Implied means a challenge, as if he is saying, "No one is more truthful than Allah in speech. If you are truthful, then bring that forth." And his saying is a specification for "most truthful." No one is more truthful than Allah in speech. Where is the speech in this verse? His saying: because truthfulness is attributed to speech. And his saying: in it is the affirmation that Allah (Mighty and Majestic) speaks and has a speech that is the most truthful of speech. And the Prophet (peace and blessings be upon him) used to say in his sermon on Friday:
The student: The most truthful of speech

The Shaykh : Yes, I think it was on Friday or on another day. He says: meaning a saying. It is like the first one, and a saying is not possible except with words. In both is the affirmation of speech for Allah (Mighty and Majestic), and that His speech is truth and veracity, with no falsehood in any way.