Those who doubted Aaron’s place as the head of the priestly line of Jacob were called to a meeting where all the tribal leaders were told to bring a rod with them. The rod of the tribe of the Levites was inscribed with Aaron’s name, as he was their tribal head. The rods were left in the tabernacle overnight. In the morning, Aaron’s rod had blossomed and had live almonds growing on it. This was to establish that Aaron was the leader of the priestly line of Israel. They kept the rod in the tabernacle as a reminder that God had chosen Aaron, and that the rest of Israel would not complain against them.
Aaron was instructed to take care of the needs of the tabernacle, and that no one should come near the service that is not a Levite. The Levites were chosen as the firstborn of the nation of Israel. Aaron and the Levites were to serve without fail.
God established His priesthood, and His leader of the tabernacle. He chose Aaron as His high priest, and then re-established the Levites as His priesthood. When God calls someone, He also establishes them. Whatever God has called you to do, trust that He will establish your path, your passage to His will, your victory over the enemy. Walk with Him and trust Him!