What does the Bible say about the role of a high priest?

In the Old Testament, the role of the high priest was critical as he represented the people before God, offering sacrifices for their sins. Aaron, appointed by God as the first high priest, serves as a vital type of Christ, who is the ultimate High Priest. Hebrews 5:4 emphasizes that no man takes this honor upon himself, but is called by God, just as Aaron was. The high priest's main function was to stand before God on behalf of the people, making atonement for their sins, which highlights the seriousness of sin and the need for a mediator.