What does the Bible say about the Lord Jesus being a priest forever?

Psalm 110:4 explicitly asserts that Jesus is a priest forever after the order of Melchizedek. This emphasizes the unique nature of Christ's priesthood compared to the Aaronic priesthood, which was temporary and ended with death. Jesus, however, possesses an unending life, enabling Him to remain our priest eternally. His priestly role is significant because it underscores His authority to intercede on behalf of His people and to offer the perfect sacrifice for their sins, fulfilling the requirements of God's justice and mercy. As the great high priest, Jesus not only offers Himself as the sacrifice but also continually represents us before the Father, ensuring our standing is secure in Him.