"Indeed, they were among Our believing servants." He means: those who affirm the Oneness of God (tawhid).
Interpretation of verses 123 through 132 of Surah al-Saffat
﴿إنَّهُمَا من عبادنَا الْمُؤمنِينَ﴾ يُرِيد المصدقين بتوحيد الله.
تَفْسِير الْآيَات من ١٢٣ وَحَتَّى ١٣٢ من سُورَة الصافات
