4 And Jehovah said to Moses, Stretch out thy hand and take it by the tail—and he stretched out his hand and caught it, and it became a staff in his hand— 5 that they may believe that Jehovah, the God of their fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath appeared unto thee. 6 And Jehovah said moreover to him, Put now thy hand into thy bosom. And he put his hand into his bosom, and took it out, and behold, his hand was leprous, as snow. 7 And he said, Put thy hand into thy bosom again. And he put his hand into his bosom again, and took it out of his bosom, and behold, it was turned again as his flesh. 8 And it shall come to pass, if they will not believe thee, neither hearken to the voice of the first sign, that they will believe the voice of the other sign. 9 And it shall come to pass, if they will not believe also those two signs, neither hearken unto thy voice, that thou shalt take of the water of the river, and pour [it] on the dry [land]; and the water that thou takest out of the river shall become blood upon the dry [land].

Matthew Henry's Commentary on Exodus 4:4-9

Commentary on Exodus 4:1-9

(Read Exodus 4:1-9)

Moses objects, that the people would not take his word, unless he showed them some sign. God gives him power to work miracles. But those who are now employed to deliver God's messages to men, need not the power to work miracles: their character and their doctrines are to be tried by that word of God to which they appeal. These miracles especially referred to the miracles of the Lord Jesus Christ. It belonged to Him only, to cast the power of the devil out of the soul, and to heal the soul of the leprosy of sin; and so it was for Him first to cast the devil out of the body, and to heal the leprosy of the body.