The response to the deniers of the message:

And the response to those who denied the message

and considered it unlikely was by the following ways:

1 - The occurrence of the message and its realization for past prophets.

{And We sent not before you except men to whom We revealed}.

{And those who disbelieve say, 'You are not a messenger.'}

Say, 'Sufficient is Allah as Witness between me and you

and whoever has knowledge of the Book.'

2 - The response to the deeming unlikely of the message and finding it strange

that it - here - is an expression of divine revelation

(which a man from mankind receives by Allah's selection of him).

{Say, 'I am only a man like you, to whom it is revealed'}.

And explaining revelation in a way that is not among impossibilities.

{And it is not for any human being that Allah should speak to him except by revelation

or from behind a partition or that He sends a messenger

to reveal by His permission what He wills. Indeed, He is Exalted and Wise}.