How do we know the priesthood of Christ is superior?

The superiority of Christ’s priesthood lies in several key aspects described in Hebrews. Unlike Aaron, who needed to offer sacrifices for his own sins, Christ had no sin and offered Himself as the perfect sacrifice for humanity's sins (Hebrews 5:3). He was designated by God with an oath, establishing His eternal priesthood in the order of Melchizedek (Hebrews 7:21). The necessity of a change in the law and priesthood underscores that Christ's priesthood supersedes the old, as it is based on the power of an endless life, unlike the mortal line of Aaron’s descendants. Therefore, Christ’s once-for-all sacrifice allows believers direct access to God and assurance of eternal acceptance.