"And whoever turns his back to them on such a day," Qatadah said: meaning, the day of Badr. "Except as a maneuver for battle," Al-Hasan said: meaning, he leaves one position for another. "Or joining a company [of his own]," meaning: he retreats to a group. "Has certainly earned wrath from Allah," meaning: he has become deserving of it.
Muhammad said: The accusative case (nasb) in His saying: "Except as a maneuver for battle" may be interpreted as a state (hal); meaning: unless someone maneuvers for the sake of fighting, and likewise for "or joining a company."
It is also permissible for the accusative case in both to be interpreted as an exception (istithna'); meaning: except for a man who is maneuvering,