long time - namely, during the desolation of Israel (Isa 32:14).
holden my peace - (Compare Psa 50:21; Hab 1:2).
cry like a travailing woman, etc. - Like a woman in parturition, who, after having restrained her breathing for a time, at last, overcome with labor pain, lets out her voice with a panting sigh; so Jehovah will give full vent to His long pent-up wrath. Translate, instead of “destroy ... devour”; I will at once breathe hard and pant, namely, giving loose to My wrath.