Aaron was the brother of Moses and high priest of the Israelites, charged with offering intercessory sacrifices on their behalf. In the latter function, he was taken in Christian typology to be a type of Christ.
In the statue at left Aaron is dressed as prescribed in Exodus 28 (cached): the breastplate with 12 stones, secured by gold chains and worn over the ephod, and the mitre with the gold plate and Hebrew inscription declaring "Holiness to the Lord."
One thing he does not wear here is the "holy crown" of Exodus 29:6 (cached). In other art, that crown has a pair of high horns that curve in toward each other (example).
In the statue shown at left, the vessel with the flame at Aaron's left foot should be the censer for the incense offering prescribed in Exodus 30:6-9 (cached). Also see Numbers 16:46: "Moses said to Aaron: Take the censer, and putting fire in it from the altar, put incense upon it, and go quickly to the people to pray for them: for already wrath is gone out from the Lord, and the plague rageth." Typologically, this intercessory role relates to Christ's reconciliation of mankind with the Father. For example, an 11th-century portable altar bears several images of intercessory sacrifices that anticipate that of Christ and, by extension, that of the Christian liturgy. In one of the images on the altar we see Aaron wielding his censer and wearing his "holy crown."
At left, Morlaiter's statue of Aaron in the church of the Gesuati (Our Lady of the Rosary), Venice.
Altarpiece of the Giving of the Ten Commandments, VeniceMenu