Aaron was selected by God as Moses’ mouthpiece (Exodus 4:14). He followed Moses, supported Moses while performing miracles before Pharoah. He was moses’ helper in leading the Israelites out of the bondage in Egypt and toward the Promised Land.
During the journey be rebels and conspires against Moses, is rebuked by God and repents.
He was chosen by God to be a priest — the high priest — (Exodus 28 & 29). He is anointed with oil and consecrated to the service of God.
Yet, when pushed by the discontented Israelites he made the golden calf for them to worship (Exodus 32) while Moses is on Sinai receiving the Ten Commandments.
Later God instructed the people how to build the tabernacle, the order of sacrifices, and Aaron begins his duties as high priest (Leviticus 9). He would go on to set the pattern of consecration instructed by God for future service for priest and the high priest (Leviticus 21).
Peter was personally called by Jesus to be a disciple (Matthew 4:18-20) and later an apostle (Matthew 10:1-2). He showed great faith in Jesus when he stated the great confession, “You are the Christ, the Son of the living God.” (Matthew 16:16).
Peter, however, was unstable. In one night he defended Jesus with a sword (Matthew 26:51) and later cursed His very name and claimed he didn’t even know Jesus (Matthew 26:69-75). The latter broke Peter’s heart.
What we saw of Peter after the Resurrection of Jesus — after he was empowered by The Holy Spirit at Pentecost was a man of valor. He preached and proclaimed to Gospel (Acts 2). He fulfilled the admonition given him by Jesus, “Feed My sheep.”
Just as after Aaron’s anointing he failed due to pressure from the grumbling Israelites, so Peter failed under the pressure of Jewish ritual. He was rebuked by Paul (Galatians 2:11-16) and finished his course — an elder and founder of Christ’s church. (1 & 2 Peter)
What do we learn from the two statesmen? The anointing of oil and the abiding presence of the Holy Spirit (which the oil represented in the O.T.) did not make these men infallible and neither is the Christian today. A Christian MUST always be submitted to the Holy Spirit if he is to be used of God for His kingdom work — for the fruit of the Spirit to be borne in the life.