Carl Friedrich Keil and Franz Delitzsch Old Testament Commentary

(Heb.: 18:42-43) Their prayer to their gods, wrung from them by their distress, and even to Jahve, was in vain, because it was for their cause, and too late put up to Him. על = על; in Psa 42:2 the two prepositions are interchanged. Since we do not pulverize dust but to dust, כּעפר is to be taken as describing the result: so that they became as dust (cf. Job 38:30, כּאכן, so that it is become like stone, and the extreme of such pregnant brevity of expression in Isa 41:2) before the wind (על־פּני as in Ch2 3:17, before the front). The second figure is to be explained differently: I emptied them out (אריקם from הריק) like the dirt of the streets, i.e., not merely: so that they became such, but as one empties it out, - thus contemptuously, ignominiously and completely (cf. Isa 10:6; Zac 10:5). The lxx renders it λεανῶ from הרק (root רק to stretch, make thin, cf. tendo tenius, dehnen dnn); and the text of 2 Sam 22 present the same idea in אדיקם.