Then I swear by the setting of the stars, (56:75)

Almuntakhab Fi Tafsir Alquran Alkarim

I swear by the location of the stars; -see introduction

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(56:75) No! *36 I swear by the positions of the stars '

Then I swear by the setting of the stars, meaning

*36) That is, "The truth is not what you seem to think it is." Here, the use of the word /a (nay) before swearing an oath by the Qur'an's being Allah's Revelation by itself shows that the oath has been sworn to refute certain objections that the disbelievers wen raising with regard to the Qur'an.
 

Then I swear by the setting of the stars, meaning in Urdu

پس نہیں، میں قسم کھاتا ہوں تاروں کے مواقع کی