Canst thou send lightnings? - That is, lightning is wholly under the control of God. So it is now; for after all that man has done to discover its laws, and to guard against it, yet still man has made no advances toward a power to wield it, nor is it possible that he ever should. It is one of the agencies in the universe that is always to be under the divine direction, and however much man may subsidize to his purposes wind, and water, and steam, and air, yet there can be no prospect that the forked lightning can be seized by human hands and directed by human skill to purposes of utility or destruction among people; compare the notes at Job 36:31-33.
And say unto thee, Here we are - Margin, "Behold us." That is, we are at your disposal. This language is derived from the condition, of servants presenting themselves at the call of their masters, and saying that they stood ready to obey their commands; compare 1-Samuel 3:4, 1-Samuel 3:6,1-Samuel 3:9; Isaiah 6:8.

Canst thou send lightnings - We have already seen that the lightning is supposed to be immediately in the hand and under the management of God. The great god of the heathen, Jupiter Brontes, is represented with the forked lightnings and thunderbolt in his hand. He seems so to grasp the bickering flame that, though it struggles for liberty, it cannot escape from his hold. Lightnings - How much like the sound of thunder is the original word: ברכים Berakim! Here are both sense and sound.
Here we are? - Will the winged lightnings be thy messengers, as they are mine?

Canst thou send lightnings, that they may go, and say unto thee, Here we are? Thy humble servants; we have been where thou didst send us, and have executed what we were bid to do, and are returned, and here we are waiting further orders; see Matthew 8:9; no; lightnings are only at the command of God, and there have been some awful instances of it, Leviticus 10:1; but not in the power of men; indeed we have an extraordinary instance in Elijah, who, at the motion, and under the impulse of the spirit of prophecy in him, called for fire, or lightning, to consume captains with their fifties, and it came down on them, and consumed them, 2-Kings 1:10; but he is not to be imitated herein: when the disciples of Christ desired the same upon a provocation, they were severely reproved by him, Luke 9:54; were these at the call and dispose of men, what dreadful things would be done in the world! for if good men, when provoked, would make use of such a power to destroy the lives of men, much more bad men; and our eyes would continually behold the flashes of lighting, and our ears hear the roarings of thunder, and the terrible effects thereof; but neither mercies nor judgments are at the command of men, but of God.

Here we are--at thy disposal (Isaiah 6:8).