"Say, who can protect you by night and by day from the Most Merciful?" meaning: they are [protected] from the Most Merciful, according to the exegesis of Qatadah; like His saying: "They protect him by the command of Allah," meaning: they are by the command of Allah, and they are guardian angels for the sons of Adam and for their deeds, and its explanation has already passed.
﴿قُلْ مَنْ يَكْلَؤُكُمْ بِاللَّيْلِ وَالنَّهَارِ من الرَّحْمَن﴾ أَيْ: هُمْ مِنَ الرَّحْمَنِ؛ فِي تَفْسِيرِ قَتَادَةَ؛ كَقَوْلِهِ: ﴿يَحْفَظُونَهُ مِنْ أَمر الله﴾ أَيْ: هُمْ مِنْ أَمْرِ اللَّهِ، وَهُمْ مَلَائِكَةٌ حَفَظَةٌ لِبَنِي آدَمَ ولأعمالهم، وَقد مضى تَفْسِيره.