It was a very great honour that Moses was called to when God commissioned him to bring Israel out of Egypt; yet he is with difficulty persuaded to accept the commission, and does it at last with great reluctance, which we should rather impute to a humble diffidence of himself and his own sufficiency than to any unbelieving distrust of God and his word and power. Note, Those whom God designs for preferment he clothes with humility; the most fit for service are the least forward.

I.Moses objects that in all probability the people would not hearken to his voice (Exo 4:1), that is, they would not take his bare word, unless he showed them some sign, which he had not been yet instructed to do. This objection cannot be justified, because it contradicts what God had said (Exo 3:18), They shall hearken to thy voice. If God says, They will, does it become Moses to say, They will not? Surely he means, "Perhaps they will not at first, or some of them will not." If there should be some gainsayers among them who would question his commission, how should he deal with them? And what course should he take to convince them? He remembered how they had once rejected him, and feared it would be so again. Note, 1. Present discouragements often arise from former disappointments. 2. Wise and good men have sometimes a worse opinion of people than they deserve. Moses sad (Exo 4:1), They will not believe me; and yet he was happily mistaken, for it is said (Exo 4:31), The people believed; but then the signs which God appointed in answer to this objection were first wrought in their sight.

II.God empowers him to work miracles, directs him to three particularly, two of which were now immediately wrought for his own satisfaction. Note, True miracles are the most convincing external proofs of a divine mission attested by them. Therefore our Saviour often appealed to his works (as Joh 5:36), and Nicodemus owns himself convinced by them, Joh 3:2. And here Moses, having a special commission given him as a judge and lawgiver to Israel, has this seal affixed to his commission, and comes supported by these credentials.

1.The rod in his hand is made the subject of a miracle, a double miracle: it is but thrown out of his hand and it becomes a serpent; he resumes it and it becomes a rod again, Exo 4:2-4. Now, (1.) Here was a divine power manifested in the change itself, that a dry stick should be turned into a living serpent, a lively one, so formidable a one that Moses himself, on whom, it should seem, it turned in some threatening manner, fled from before it, though we may suppose, in that desert, serpents were no strange things to him; but what was produced miraculously was always the best and strongest of the kind, as the water turned to wine: and, then, that this living serpent should be turned into a dry stick again, this was the Lord's doing. (2.) Here was an honour put upon Moses, that this change was wrought upon his throwing it down and taking it up, without any spell, or charm, or incantation: his being empowered thus to act under God, out of the common course of nature and providence, was a demonstration of his authority, under God, to settle a new dispensation of the kingdom of grace. We cannot imagine that the God of truth would delegate such a power as this to an impostor. (3.) There was a significancy in the miracle itself. Pharaoh had turned the rod of Israel into a serpent, representing them as dangerous (Exo 1:10), causing their belly to cleave to the dust, and seeking their ruin; but now they should be turned into a rod again: or, thus Pharaoh had turned the rod of government into the serpent of oppression, from which Moses had himself fled into Midian; but by the agency of Moses the scene was altered again. (4.) There was a direct tendency in it to convince the children of Israel that Moses was indeed sent of God to do what he did, Exo 4:5. Miracles were for signs to those that believed not, Co1 14:22.

2.His hand itself is next made the subject of a miracle. He puts it once into his bosom, and takes it out leprous; he puts it again into the same place, and takes it out well, Exo 4:6, Exo 4:7. This signified, (1.) That Moses, by the power of God, should bring sore diseases upon Egypt, and that, at his prayer, they should be removed. (2.) That whereas the Israelites in Egypt had become leprous, polluted by sin, and almost consumed by oppression (a leper is as one dead, Num 12:12), by being taken into the bosom of Moses they should be cleansed and cured, and have all their grievances redressed. (3.) That Moses was not to work miracles by his own power, nor for his own praise, but by the power of God and for his glory; the leprous hand of Moses does for ever exclude boasting. Now it was supposed that, if the former sign did not convince, this latter would. Note, God is willing more abundantly to show the truth of his word, and is not sparing in his proofs; the multitude and variety of the miracles corroborate the evidence.

3.He is directed, when he shall come to Egypt, to turn some of the water of the river into blood, Exo 4:9. This was done, at first, as a sign, but, not gaining due credit with Pharaoh, the whole river was afterwards turned into blood, and then it became a plague. He is ordered to work this miracle in case they would not be convinced by the other two. Note, Unbelief shall be left inexcusable, and convicted of a wilful obstinacy. As to the people of Israel, God had said (Exo 3:18), They shall hearken; yet he appoints these miracles to be wrought for their conviction, for he that has ordained the end has ordained the means.

They will not believe me - As if he had said, Unless I be enabled to work miracles, and give them proofs by extraordinary works as well as by words, they will not believe that thou hast sent me.

And Moses answered and said,.... In reference to what Jehovah had declared to him in the latter end of the preceding chapter:

but, behold, they will not believe me, nor hearken to my voice; this seems to contradict what God had said to him, Exo 3:18 that they would hearken to his voice; but it can hardly be thought, that so good a man, and so great a prophet as Moses was, would directly fly in the face of God, and expressly contradict what he had said. To reconcile this it may be observed, that what the Lord says respects only the elders of Israel, this all the people; or Jehovah's meaning may be, and so this of Moses, that neither the one nor the other would regard his bare word, without some sign or miracle being wrought; for as his call was extraordinary, so it required something extraordinary to be done that it might be credited:

for they will say, the Lord hath not appeared unto me: in the bush, as he would affirm he did, and might do it with the greatest assurance; yet the thing being so marvellous, and they not eyewitnesses of it, might distrust the truth of it, or be backward to receive it on his bare word; and this Moses might rather fear would be the case, from the experience he had had of them forty years ago, when it was more likely for him to have been a deliverer of them.