Aaron is best known for his role in the exodus and for being the first of the Levitical, or Aaronic, priesthood. He was born to a family of Levites during Israel's enslavement in Egypt and was Moses' older brother, three years his senior (Exodus 7:7). We are first introduced to Aaron in Exodus 4 when God tells Moses that He will send Aaron, Moses' brother, with him to free the Israelites from Pharaoh.

The Israelites remained in Egypt after Joseph and his generation died, and they became quite numerous. A new Pharaoh feared the Israelites would rise up against the Egyptians, so he put slave masters over them and enacted harsh laws (Exodus 1:8–14). He also ordered the Hebrew midwives to kill all the baby boys as soon as they were born. When the midwives refused, Pharaoh ordered all the people to throw the Hebrew male infants into the Nile. These laws had been enacted by the time Moses was born. Presumably Aaron was born prior to the laws, or he escaped death because the midwives feared God rather than obeyed Pharaoh (Exodus 1:15–22). We read nothing of Aaron until God sends him to the eighty-year-old Moses.

When God spoke to Moses through a burning bush, calling him to go back to Egypt and demand that Pharaoh free the Israelites (Exodus 3—4), Moses gave reasons why he was not a good choice for the job. Moses eventually requested that God send someone else (Exodus 4:13). "Then the LORD’s anger burned against Moses and he said, 'What about your brother, Aaron the Levite? I know he can speak well. He is already on his way to meet you, and he will be glad to see you’" (Exodus 4:14). God went on to tell Moses that Aaron would be Moses' spokesperson (Exodus 4:15–17).

God also spoke to Aaron, telling him to meet Moses in the wilderness. Aaron obediently went. Moses told Aaron what God had said, including God's instructions about the signs they would perform in front of Pharaoh. In Egypt, Moses and Aaron gathered the elders of the Israelites, and Aaron told them what God had said to Moses (Exodus 4:27–31). It is interesting to note how quickly Aaron responded to God in obedience and how he quickly believed what Moses told him. Aaron seemed to be up to the task to which God called him without question, willingly helping his brother and speaking to the people on his behalf. Aaron perhaps also served as an intermediary between Moses and the Israelites, since Moses had been living apart from his people all his life—first in the Egyptian courts and then as a fugitive in Midian.

As the exodus story unfolds, we see both Moses and Aaron before Pharaoh, making their requests for Pharaoh to let the people go and performing many signs. God used Aaron's staff in many of the signs and plagues. The men were obedient to God's instructions, and the Israelites were ultimately freed.

Aaron continued to lead with Moses during the Israelites' desert wandering, serving somewhat as his aid and spokesperson. When the Israelites grumbled against Moses and Aaron (Exodus 16:2), "Moses and Aaron said to all the Israelites, 'In the evening you will know that it was the Lord who brought you out of Egypt, and in the morning you will see the glory of the LORD, because he has heard your grumbling against him. Who are we, that you should grumble against us?'" (Exodus 16:6–. Moses told Aaron to call the people together to come before the Lord, and the glory of the Lord appeared before them in a cloud (Exodus 16:10). It was at this time that God provided quail and manna. God instructed Moses to keep an omer of manna in a jar that would be kept for generations to come; Moses asked Aaron to collect it (Exodus 16:32–35).

In the aftermath of Korah’s rebellion against Moses and Aaron, God performed a miracle to confirm that Aaron and his descendants were indeed chosen to minister before the Lord’s presence. Twelve staffs were collected, one from each tribe. The staff representing the tribe of Levi had Aaron’s name inscribed on it. The staffs were laid in the tabernacle in front of the ark of the covenant overnight, and the next morning Aaron’s staff “had not only sprouted but had budded, blossomed and produced almonds” (Numbers 17:. God commanded Moses to place Aaron’s staff inside the ark as well, saying, “This will put an end to their grumbling against me” (verse 10).

During a battle with the Amelekites, Joshua, the commander of the Israelite army, had victory only when Moses' hands were raised. Moses became fatigued, so Aaron and Hur put a stone under him and held up his hands. In many ways, this is a picture of much of Aaron's service to Moses. He supported his brother, whom God had chosen to lead the Israelites out of captivity.

At Mount Sinai, God warned the people to keep their distance as God met with Moses and gave him the Law. On one of Moses’ ascents, God told him to bring Aaron with him (Exodus 19:24). Later, when Moses stayed on the mountain with God, he put Aaron and Hur in charge to handle any disputes that might arise (Exodus 24:14).

Unfortunately, things did not go well for Aaron while he was in charge. The people became impatient waiting for Moses to return and asked Aaron to make them a god. Seemingly without resistance to the people's urge, Aaron requested their golden jewelry, formed it into the shape of a calf, and created an idol. Aaron even built an altar in front of the calf and announced a festival for it (Exodus 32:1–6). It may seem difficult to understand how a man who had so willingly obeyed God's call to help his brother lead the people out of Egypt, seen God's amazing works firsthand, and just recently seen God on Mount Sinai could do such a thing. Aaron's failure is a demonstration of our human natures. We don't know Aaron's motivation, but it is not hard to imagine that he might have doubted God and feared the people.

When God told Moses what was happening with the people and the golden calf, He threatened to destroy the people and make a great nation out of Moses instead. Moses intervened on behalf of the people and returned to them (Exodus 32:7–18). When Moses actually saw what was occurring, "his anger burned and he threw the tablets out of his hands, breaking them to pieces at the foot of the mountain" (Exodus 32:19). The tablets contained God's covenant; it seems Moses destroyed them not just in a moment of anger, but also because the people had broken the covenant through their disobedience. Moses burned the idol, scattered its ashes in the water, and made the Israelites drink it (Exodus 32:20). When Moses asked Aaron why the people had done this and why he'd led them into it, Aaron was honest about the people's complaining and request for him to make a god, but he was not forthcoming about his own role. Aaron admitted to his collection of their jewelry but claimed that, when he "threw it into the fire, . . . out came this calf!" (Exodus 32:24). "Moses saw that the people were running wild and that Aaron had let them get out of control and so become a laughingstock to their enemies" (Exodus 32:25). Moses called those who were for the Lord to him. The Levites rallied to him, and then Moses instructed them to kill some of the people. Moses, again, interceded for the people. God reassured Moses but also sent a plague on the people for their sin (Exodus 32:33–35).

The golden calf incident was not Aaron's only blunder. In Numbers 12 Aaron and Miriam (Aaron and Moses' sister) oppose Moses: "Miriam and Aaron began to talk against Moses because of his Cushite wife, for he had married a Cushite. ‘Has the Lord spoken only through Moses?' they asked. 'Hasn't he also spoken through us?'" (Numbers 12:1–2). Such pride is not godly, but it is a common danger among leaders; many of us perhaps relate with Aaron. God called the three siblings out to meet Him, defended Moses to Aaron and Miriam, and asked why Aaron and Miriam hadn't been afraid to speak against him. When the cloud from which the Lord spoke lifted, Miriam was leprous. Aaron pleaded with Moses on her behalf; Moses cried out to God, and, after seven days outside the camp, Miriam was healed (Numbers 12:3–16). It is interesting that Miriam suffered leprosy whereas Aaron did not. It is also interesting to see Aaron's plea to Moses, acknowledging his foolish sin and asking him not to allow Miriam to suffer. It seems that Aaron was truly repentant.

Aaron and his sons were appointed by God to be priests for the people, and Aaron was the first high priest. God gave Moses commandments about the priesthood, including how to consecrate priests and what garments they should wear, on Mount Sinai. God told Moses that the priesthood would belong to Aaron and his descendants by lasting ordinance (Exodus 29:9). Aaron was made the high priest, and his family line continued to serve as priests until the destruction of the temple in AD 70. The New Testament book of Hebrews spends much time comparing Jesus' permanent priesthood to the Aaronic priesthood. Priests of the Levitical line had to offer sacrifices for their own sins and sacrifices on behalf of the people continually. Jesus was without sin, and His sacrifice on behalf of the people was made once and is finished (see Hebrews 4—10).

While Aaron's sons did follow him into the priesthood, two of his sons—Nadab and Abihu—were killed by God when they offered "unauthorized fire before the LORD, contrary to his command" (Leviticus 10:1). When Moses told Aaron that this is what God meant when He said He would be proved holy, Aaron remained silent (Leviticus 10:3). Aaron did not try to defend his sons, nor did he accuse God of wrongdoing. It seems Aaron truly understood God's holiness and accepted His judgment on his sons.

Like Moses, Aaron was not permitted to enter the Promised Land due to their sin at Meribah (Numbers 20:23). God instructed Moses, Aaron, and Aaron's son Eleazar to go up Mount Hor. There Eleazer would be made high priest, and Aaron would die (Numbers 20:26–29).

Aaron's life is a demonstration of God's holiness and His grace. Aaron began as an obedient and faithful servant, willingly going to Moses and serving as an intermediary. He also faithfully served as a priest in the sacrificial system God used as a picture for His ultimate plan of salvation in Jesus Christ. Like any other human, Aaron was a sinner. After having seen God's mighty work, he still made the golden calf and led the people in worshipping it. But Aaron seems to have learned and grown, admitting his sin in speaking against Moses and accepting the deaths of his unfaithful sons. From Aaron we learn about serving others, sharing in the responsibility of leadership, and submitting to God.