Al-Ma'aarij • BN-TAFSEER-IBN-E-KASEER
﴿ فَلَآ أُقْسِمُ بِرَبِّ ٱلْمَشَٰرِقِ وَٱلْمَغَٰرِبِ إِنَّا لَقَٰدِرُونَ ﴾
“But nay! I call to witness [Our being] the Sustainer of all the points of sunrise and sunset: verily, well able are We”
Please check ayah 70:44 for complete tafsir.