What is the interpretation of the verse: (And if you could but see when the angels take the souls of those who disbelieve, striking their faces and their backs and [saying], "Taste the punishment of the Burning Fire"), and can the warning contained therein apply to some Muslims, especially the striking?

The meaning of "if you could see": if you could perceive. The answer to "if" is omitted and its تقدير (estimation) is "you would see something wondrous." "He takes their souls": He seizes their spirits. "They strike their faces and their backs": They strike them from the front and the back. The meaning of "and taste the punishment of burning": They strike them and say to them, "Taste the scorching punishment." This verse was revealed concerning the disbelievers at Badr, and the marks of the striking were seen on the back of Abu Jahl. Muslims are not included in this threat.