What is the significance of Aaron's rod?

In the Bible, rods and staffs play a significant role. For instance, shepherds used their staffs to direct their sheep (Psa. 23:4). A staff (Heb. mish'enah) is a long slender stick with a hook on one end. It was used primarily to guide sheep, but also to lift a separated newborn and bring it back to its mother. Shepherds also would carry rods (Heb. shebet) which, in that era, conveyed authority, power, and discipline, but they were also used as a defensive weapon. It was a club-like device and was normally shorter than a staff.

Elsewhere in Scripture, the Hebrew word may differ and be interpreted as either a rod or a staff. Such is the case with Moses’s rod/staff (Heb. matteh) in Exodus 4:2 and Aaron’s rod/staff (Heb. matteh) in Exodus 7:9. Moses used a staff—the rod of God (Exod. 4:20)—to lead the Israelites out of Egypt (Exod. 4:1-5; Num. 20:11), and used it later as well (Num. 17:5, 8).

Aaron used a rod to assist his brother Moses and Israel. By the power of the Holy Spirt, Aaron’s rod was turned into a snake in Pharaoh’s court that swallowed the Egyptian priest’s snakes (Exod. 7:8-10). Aaron’s rod was used during the ten plagues to turn water into blood (Exod. 7:19-21), to bring frogs (Exod. 8:5-6), and gnats (Exod. 8:16-17). Ultimately, Aaron’s rod was placed before the Lord in the ark of the covenant (Num. 17:10; Heb. 9:4) as a sign against those who would rebel against the Lord.

When God does his miracles, signs and wonders, he is free to use whatever means he chooses. While he didn’t need rods or staffs to accomplish his will, he did choose to use them. Why? We know that many ancient Near East religions and persons of authority in that era carried rods or staffs. It's likely that by using a rod or staff in his ordination of signs, God was showing not only his power and authority but especially that he was the King of kings, the King with absolute and ultimate power and authority. In Hebrew this is expressed as Melech Malchei HaMelachim or the Kings of Kings of Kings.