How is Mormon priesthood different from biblical priesthood of the saints?

from the old testament

• The Old Testament priesthood was established directly by God under the Mosaic covenant. God chose Aaron and his descendants from the tribe of Levi to serve as priests and represent Israel before Him (Exodus 28:1; Numbers 3:5–10). Their responsibilities included offering sacrifices, maintaining the tabernacle and later the temple, teaching God's Law, and interceding for the people (Leviticus 1–7; Deuteronomy 33:8–10).
• The Levitical priesthood was never intended to be permanent. Its sacrifices had to be repeated continually because they could never fully remove sin (Leviticus 16; Hebrews 10:1–4). God also promised a different and greater priesthood through the coming Messiah. Psalm 110:4 declares, "You are a priest forever after the order of Melchizedek," pointing to a priesthood that would surpass the temporary Levitical system.
  
• The Old Testament anticipated a new covenant in which God would transform His people from within rather than relying on external ceremonies alone (Jeremiah 31:31–34; Ezekiel 36:25–27). The prophets looked forward to a day when God's people would know Him personally and receive forgiveness through His gracious work.
  
• Although Israel had ordained priests, the entire nation was also called to represent God before the world. At Mount Sinai, God declared that Israel would be "a kingdom of priests and a holy nation" if they obeyed His covenant (Exodus 19:5–6). This foreshadowed the New Testament fulfillment that all believers would become a royal priesthood through Christ.
  
• Most importantly, the Old Testament never teaches that priesthood authority would disappear from the earth and later need to be restored centuries afterward. Instead, it points forward to the Messiah, whose priesthood would be eternal and complete (Psalm 110:4).

from the new testament

• The New Testament declares that Jesus fulfilled everything the Old Testament priesthood anticipated. Unlike the Levitical priests, who continually offered sacrifices for sin, Jesus offered Himself once for all and now serves forever as our eternal High Priest (Hebrews 7:23–28; 9:11–14; 10:11–14). Because His sacrifice is complete, no additional priesthood is needed to provide access to God.
• Jesus gives all who trust in Him for the forgiveness of sins direct access to the Father. Hebrews invites Christians to "draw near with confidence to the throne of grace" because of Christ's priestly work (Hebrews 4:14–16; 10:19–22). Believers do not need another human priest to mediate forgiveness or God's presence.
  
• The New Testament teaches the priesthood of all believers. Peter writes that Christians are "a holy priesthood" who offer "spiritual sacrifices acceptable to God through Jesus Christ" and later calls them "a royal priesthood" (1 Peter 2:5, 9). These spiritual sacrifices include worship (Hebrews 13:15), obedience (Romans 12:1), generosity (Hebrews 13:16), prayer, and proclaiming the gospel. Every believer shares this privilege because every believer belongs to Christ.
• The New Testament distinguishes between spiritual gifts and church leadership without describing either as a restored priesthood. Christ gave apostles, prophets, evangelists, pastors, and teachers to equip the church (Ephesians 4:11–13). Elders and deacons serve important leadership roles (1 Timothy 3:1–13; Titus 1:5–9), but they are never described as possessing a higher priesthood that grants unique authority to perform saving ordinances or mediate God's grace.
• The New Testament also teaches that the Holy Spirit indwells every believer and distributes gifts according to God's will without any human intermediary (1 Corinthians 12:4–11). Ministry flows from union with Christ and the empowering work of the Spirit rather than from receiving priesthood authority through a lineage or restoration.
  
• By contrast, the Mormon Church teaches that priesthood authority was lost after the death of the apostles during a "Great Apostasy" and restored to Joseph Smith in the nineteenth century. It teaches two priesthood orders—the Aaronic Priesthood and the Melchizedek Priesthood—which are conferred upon worthy male members and are considered necessary for administering ordinances with divine authority. The Bible, however, never speaks of such a loss of priesthood authority, nor does it teach that Christ's eternal priesthood would require restoration. Instead, it emphasizes that Christ's priesthood is everlasting (Hebrews 7:24–25), that His sacrifice is sufficient (Hebrews 10:12–14), and that every believer has direct access to God through Him (1 Peter 2:9; Hebrews 10:19–22).

implications for today

At the heart of the difference between Mormon priesthood and the biblical priesthood of believers is a question: Do we need a restored human priesthood to access God, or has Jesus already accomplished everything necessary to bring us to Him? Mormon teaching emphasizes that priesthood authority was lost and later restored through Joseph Smith, with certain ordinances requiring this priesthood authority. The Bible, however, teaches that Jesus’ priesthood is not missing, incomplete, or waiting to be restored—it never has been. Jesus' priesthood is eternal, perfect, and sufficient (Hebrews 7:24–25). Because Christ offered the final sacrifice for sin, believers do not need another mediator, another priestly line, or another authority structure to approach God (Hebrews 10:11–14, 19–22).

Much like the rest of Mormonism, the Mormon understanding of the priesthood elevates a select group of believers above others, conferred on by other men who speak on behalf of God. The Bible, however, tells us that all who belong to Christ are a “royal priesthood” with direct access to God and a calling to represent Him in the world (1 Peter 2:9). Second Corinthians 5:20 tells us what that means: "Therefore, we are ambassadors for Christ, God making his appeal through us. We implore you on behalf of Christ, be reconciled to God."

Christians do not need a special title, office, or human mediator to serve God; through the Holy Spirit, every believer is equipped to pray, worship, share the gospel, encourage others, and offer their lives as a living sacrifice to God. The greatest privilege is not receiving a priesthood title. It is knowing that Jesus Himself has made the way to the Father and getting to represent Him to a world that desperately needs Him.