For their rock is not as our Rock, even our enemies themselves being judges. For their rock - The gods and pretended protectors of the Romans.
Is not as our Rock - Have neither power nor influence like our God.
Our enemies themselves being judges - For they often acknowledged the irresistible power of that God who fought for Israel. See Exodus 14:25; Numbers 23:8-12, Numbers 23:19-21; 1 Samuel 4:8.
There is a passage in Virgil, Eclog. iv., ver. 58, very similar to this saying of Moses: -
Pan Deus Arcadia mecum si judice certet,
Pan etiam Arcadia dicat se judice victum.
"Should the god Pan contend with me," (in singing
the praises of the future hero, the deliverer,
prophesied of in the Sibylline books), "were even
Arcadia judge, Pan would acknowledge himself to be
vanquished, Arcadia herself being judge."