As-Saffat: 26

"Nay, they are that day submissive [mustaslimun]"

[They are] led by their helplessness and the blocking of all stratagems against them. The root of istislam (submission) is the seeking of safety, and compliance is an implication of that by convention; therefore, it is used in this context. Or, it may mean mutasalimun (mutually surrendering), as if they are surrendering one another to destruction and abandoning each other.

It is also permitted that the disjunctive particle (bal) serves to turn away from the implication of what preceded it—meaning they do not dispute regarding the standing [on the Day of Judgment] or other matters, but rather they comply or abandon one another—or [it turns away] from His saying, Exalted is He, "They shall not help one another," meaning: not only are they unable to help one another, but they are also submissive to the torment or rendered subservient.