His saying: "By the star when it descends." The Tafsir of Ibn Abbas states: He says, "Meaning the revelation when it descends." In the Tafsir of al-Hasan: It means the stars when they are scattered. The "star" (al-najm) according to him is the collection of stars by which He swore.
قَوْله: ﴿النَّجْم إِذا هوى﴾ تَفْسِير ابْن عباسٍ قَالَ: يَقُول: وَالْوَحي إِذا نزل وَفِي تَفْسِير الْحسن: يَعْنِي الْكَوَاكِب إِذا انتثرت. والنجم عِنْده: جمَاعَة النُّجُوم أقسم بِهِ