How do we know the doctrine of Jesus as high priest is true?

The doctrine of Jesus as our high priest is rooted in the biblical text, especially Hebrews 7, which contrasts Jesus' priesthood with the Levitical priesthood. The author of Hebrews argues that if the Levitical priests could achieve perfection, then there would be no need for another priest after the order of Melchizedek. However, since perfection cannot come from the law and the Levitical priests, Jesus, who was designated as a high priest by God, fulfills this unique role. This is confirmed through prophetic texts that forecast a priest who embodies both kingship and priesthood, ultimately culminating in Jesus Christ.