I say:

On the assumption that Muhammad, may Allah bless him and grant him peace, is the one addressed, there are two interpretations. The first is Qatāda’s. He said concerning “What, then, makes you deny the Recompense after this?”: “That is, be certain, for clarification has come to you from Allah.” This is how Ibn Abī Hātim transmitted it from him through a reliable chain of transmission.

Al-Mahdawī likewise cited it:

“‘What, then, makes you deny the Recompense after this?’ That is, be certain, in light of what has come to you from Allah, that He is the wisest of judges. Thus, the Prophet, may Allah bless him and grant him peace, is the one addressed.”

He attributed this interpretation to Qatāda, then said:

“It has also been said that the meaning is: ‘What, then, makes you deny, O you who doubt Allah’s power?’—meaning the disbelievers. What induces you to do so after His power has become clear to you?”

He said: “Al-Farrā’ said: ‘Who, then, can declare you a liar concerning reward and punishment?’ This is the interpretation preferred by al-Tabarī.”

(I say:

This interpretation transmitted from Qatāda is what caused Mujāhid to recoil from the view that the Prophet, may Allah bless him and grant him peace, was being addressed. As various scholars, including Ibn Abī Hātim, transmitted from al-Thawrī, from Mansūr, who said:

“I asked Mujāhid: ‘In “What, then, makes you deny the Recompense after this?”, did He mean the Prophet, may Allah bless him and grant him peace?’

“He replied: ‘Allah forbid! He meant man.’”

Mujāhid was right to hold the Prophet, may Allah bless him and grant him peace, above being told, “What, then, makes you deny?”—meaning, “Be certain and do not deny.” For if he were told, “Do not deny,”