Adam Clarke on Exodus 18:18

Thou wilt surely wear away - נבל תבל nabol tibbol, in wearing way, thou wilt wear away - by being thus continually employed, thou wilt soon become finally exhausted. And this people that is with thee; as if he had said, "Many of them are obliged to wait so long for the determination of their suit that their patience must be soon necessarily worn out, as there is no one to hear every cause but thyself."