With the name of Allah Most Gracious, Most Merciful
Sura 53 (Najm)
“By the star when it goes down.
Your companion does not err, nor does he go astray;
Nor does he speak out of desire.
It is naught but inspiration which is inspired.”
This sura commences by Allah SWT taking an oath on natural phenomena, in this case the setting of the stars. As much as the setting of the star is true so are the statements that follow. The rejecters accused Muhammad saw of being possessed or having fabricated the Quran. Allah SWT informs them that this is not the case, he has not strayed nor erred but the words he speaks are through Divine inspiration. It was the Divine inspiration (Al Quran) that people doubted hence Allah SWT informs them that these specific words of Muhammad SAW come through Divine inspiration.
Cross reference: sura 21 verse 45
Continues tomorrow… InshaAllah