Aaron's rod refers to any of the staves carried by Moses 's brother, Aaron . The Bible tells how, along with Moses's rod, Aaron's rod was endowed with miraculous power during the Plagues of Egypt that preceded the Exodus. There are two occasions where the Bible tells of the rod's power.
Biblical references
The Rod of Aaron Devours the Other Rods
In the culture of the Israelites , and the rod was a natural symbol of authority, as the tool used by the shepherd to correct and guide his flock . Moses's rod is, in fact, cited in Exodus 4:2 as carried by him while he tended his sheep; and later becomes his symbol of authority over the Israelites. The rods of both Moses and Aaron were endowed with miraculous power during those time. God commanded Moses to raise his rod over the Red Sea when it was to be parted and in prayer over Israel in battle; Moses brings forth water from a stone using his rod.
Aaron's rod, however, is cited twice as exhibiting miraculous power on its own, when not physically in the grasp of its owner. God sends Moses and Aaron to the Pharaoh once more, instructing Aaron that when the Pharaoh demands to see a miracle, he is to "cast down his rod" and it will become a serpent . When he does so, the Pharaoh's sorcerers counter by similarly casting down their own rods, which also become serpents, but Aaron's rod swallows them all. "The Pharaoh's heart is stubborn" and he chooses to ignore this bit of symbolic warning, and so the Plagues of Egypt ensue. Notably, this chapter begins with God telling Moses, "Behold, I have made you as God to the Pharaoh and your brother Aaron will be your prophet." As God transmits his word through his prophets to his people, so Moses will transmit God's message through Aaron to the Pharaoh. The prophet's task was to speak God's word on God's behalf. He was God's "mouth".