After it a voice roareth: he thundereth with the voice of his excellency; and he will not stay them when his voice is heard.
After it - after the lightning the voice roareth. The thunder-clap follows at an interval after the flash.
Stay them - He will not hold back the lightnings (Job 37:3) when the thunder is heard (Maurer). Or, not so well, take 'them' as the usual concomitants of thunder-namely, rain and hail (Umbreit). (Job 40:9.)