Exodus 4:5

That they may believe
The elders and people of Israel; for this miracle was wrought not for the confirmation of Moses's faith; for, as Aben Ezra observes, the sign of the burning bush was given to him to confirm his faith, that it was God that appeared to him, and called him to this work; but this was wrought to confirm the faith of the Israelites in his divine mission: that the Lord God of their fathers, the God of Abraham, the God of
Isaac, and the God of Jacob, hath appeared unto thee;
(See Gill on Exodus 3:6).