He—glorified be He—has made it clear that the signs do in fact reach them, yet whenever a sign comes to them they turn away from it. By denying the truth, they will ultimately come to witness the authenticity of what the Messenger has brought, just as He destroyed those before them for their sins, namely their rejection of the Messenger.

For Allah says:
“Your Lord would never destroy the towns until He had raised in their mother-city a messenger reciting Our revelations to them; nor would We ever destroy the towns unless their people were wrongdoers.” [al-Qasas 28:59]

He has further shown the depth of their disbelief: even if We were to send down to them a Book on parchment so that they could touch it with their own hands, those who disbelieve would still say, “This is nothing but unmistakable sorcery.” He—exalted is He—has also made plain that had He appointed the Messenger an angel, He would still have sent him in the form of a man, for they are unable to behold angels in their true forms; in that case the same confusion would arise, for they would assume the Messenger was merely a human and not an angel.

The Exalted said:
“They say, ‘We will never believe in you until you cause a spring to gush for us from the earth,’” [al-Isrāʾ 17:90] (90)

“or until you have a garden of date-palms and grapes and make rivers flow abundantly through it,” [al-Isrāʾ 17:91] (91)

“or until you cause the sky, as you claim, to fall upon us in pieces, or bring Allah and the angels before us face to face,” [al-Isrāʾ 17:92] (92)

“or until you have a house adorned with gold, or you ascend into the heavens—and even then we will not believe in your ascent until you bring down for us a Book we can read.’ Say, ‘Glory be to my Lord! I am nothing but a human messenger.’” [al-Isrāʾ 17:93] (93)

“And nothing prevented people from believing when guidance came to them except their saying, ‘Has Allah sent a human as a messenger?’” [al-Isrāʾ 17:94] (94)

“Say, ‘If there had been angels walking about on earth in tranquility, We would certainly have sent down to them an angel from the heavens as a messenger.’” [al-Isrāʾ 17:95] (95)