The function of priests, as outlined, centers on their role as intermediaries between God and the people, embodying and promoting holiness. Priests, through their religious instruction and living example, combined with the services conducted at the tabernacle or temple, are called by God to be constant reminders to the entire nation and church that everyone is to be holy as God is holy. Their responsibilities include offering gifts and sacrifices for sins, acting on behalf of men before God, since men are personally cut off from direct access to Him in the context of worship arrangements. Under the Old Covenant, priests and Levites were visible and audible links between God's call to holiness and its fulfillment in His Kingdom. Aaron was appointed as high priest, and his sons—Nadab, Abihu, Eleazar, and Ithamar—as priests, to organize Israel toward becoming a holy nation. Their roles demanded strict adherence to God's standards, with no deviations or innovations permitted, as seen in the severe consequences faced by Nadab and Abihu for offering profane fire. Physical perfection was required, disqualifying those with defects from serving at the altar until healed, reflecting the perfection of God Whom they represented. Priests were also bound by stringent ceremonial and personal conduct rules, such as restrictions on contact with the dead, marriage to virgins from their own lineage, and abstaining from practices associated with pagans, all to maintain their holiness. Under the New Covenant, all believers are considered a royal priesthood, serving under the High Priest, Jesus Christ. They are to be visible and audible links in the same purpose of holiness, acting as priests to each other with responsibilities to reflect God's holiness in conduct and attitude before Him, the world, and the church. The Old Testament records of priestly duties and standards are deliberately designed for learning, emphasizing the high level of holiness God demands from those called to serve Him in such intimate association with the Father, the Son, and each other within His family.

The function of priests is a vital aspect of God's plan, as we are called to be a royal priesthood, both now and in the future Kingdom of God. Revelation 5:10 declares that we are made kings and priests to our God and shall reign on the earth, highlighting the dual role we are to prepare for. This priestly responsibility is not merely a future expectation but a present reality, as I Peter 2:9 and 2:5 affirm that we are a chosen generation, a royal priesthood, built as living stones into a spiritual house to offer spiritual sacrifices acceptable to God through Jesus Christ. These sacrifices are not just for the future; we must practice them now to be prepared for our roles in the World Tomorrow. A priest's primary function is to assist people in accessing God, facilitating union with Him through mediation and reconciliation between God and men. This role involves being a mediator who brings together, reconciling differences, and also serving as a teacher of a way of life to improve upon the established reconciliation. In the Old Testament, priests had unique access to God, entering areas of the Temple such as the Holy Place, and on the Day of Atonement, the high priest entered the Holy of Holies to make offerings before God. This access allowed priests to serve God personally and minister to others by representing the average Israelite before God, offering something of value to both parties. Priests also offer sacrifices, a central duty seen in the vast number of offerings required during the Feast of Tabernacles, which symbolizes the Millennium. Numbers 29:12-13 details the extensive sacrifices during this feast, indicating the significant priestly work that will be required in the future, surpassing all other times in God's plan. While physical animal sacrifices were offered in the past, the concept now extends to spiritual sacrifices, reflecting dedication and service. Additionally, priests function as saviors and judges, as seen in Obadiah 21, where saviors on Mount Zion judge during the millennial period, delivering and teaching Israel as they are regathered from captivity. The essence of sacrifice, a key priestly act, is to give a gift to God to establish or renew fellowship with Him. Sacrifices are not merely about death but include the offering of a life lived in devotion, commitment, and service. Romans 12:1 urges us to present our bodies as a living sacrifice, holy and acceptable to God, which is our reasonable service. This mirrors the example of Jesus Christ, who offered His life entirely in obedience to God, setting a pattern for us to follow as New Testament priests preparing for our future roles. Through such sacrifices, we build and strengthen our relationship with God, renewing it daily to maintain at-one-ment with Him.

Priests in ancient Israel consisted of all qualified males from the tribe of Levi, with high priests drawn from Aaron's family. God claimed the entire tribe of Levi for lifelong service devoted to maintaining correct worship first in the tabernacle and later in the temple. Levitical priests were required to meet strict standards of physical and moral purity before offering sacrifices. Physical perfection was demanded so that no priest with defects such as blindness, lameness, deformity, disease, or injury could approach the altar or the veil, since such imperfections represented the effects of sin and would profane God's sanctuary. Within this tribe Aaron and his descendants held special status as high priests with the highest responsibility to serve in the holy place and the most holy place. The function of the priest was to build a bridge between man and God. Priests represented God before the people and the people before God while guarding and defending His truth and creation. Although not every Israelite ministered in the tabernacle or temple, the entire nation functioned in a priestly capacity by representing God to surrounding nations and performing duties in support of the priesthood. Adam's original responsibilities of guarding the garden, upholding Sabbath observance, and protecting creation from defilement illustrate these same priestly functions. This physical priesthood served as a shadow of the spiritual royal priesthood that is the church. Members of the church are called to offer spiritual sacrifices acceptable to God through Jesus Christ, who as the perfect High Priest purifies His people continuously and introduces them into the Father's presence. Their priestly duties include presenting themselves as living sacrifices, maintaining purity of heart and conduct, stirring up love and good works among one another, and assembling faithfully for worship and encouragement. These responsibilities demand sincere reverence, consistent obedience, and freedom from attitudes of contempt, weariness, hypocrisy, or presumption toward God's service.

Priests stand between God and worshippers as agents provided by Him for the purpose of helping worshippers by means of instruction and example to become holy as God is holy. Growing in holiness through the sanctification process is the single most important requirement for filling the priestly position because the position is so important. Holiness reflects a similitude of God. Under both the Old and New Covenants God's overall purpose is to create a holy nation. All are called to be part of the priesthood and are in training for that responsibility. The priest promotes unity of the brethren by being in unity with God. This unity flows from the Father through the Son through the priesthood and out to those the priesthood is serving. The priest promotes conduct among the brethren that is in harmony with the responsibilities of the relationship with God. Humility meekness patience and forbearing with one another in love produce holiness because this quality of unity holds things together. The love for God and the brethren motivates the priest's conduct. A priest must study God's Word and put it into practice because the Word of God is essential to the life and work of a priest. The Word cleanses the mind. Every high priest is appointed for men in things pertaining to God that he may offer both gifts and sacrifices for sins. He can have compassion on those who are ignorant and going astray. No man takes this honor to himself but he who is called by God. The priest must be attuned to God's Word and the appeals of the people so that he can get to the heart of a matter and rightly counsel people. The priest must handle responsibilities in a consecrated way and walk before the people in an upright and holy manner.

Priests function as mediators who serve God in His house by maintaining constant visible submission through head coverings that symbolize authority under the divine resident. The high priest's white turban and golden crown engraved "HOLINESS TO THE LORD," positioned across the forehead as the seat of reasoning and will, continually directs thought, attitude, speech, and conduct toward that single standard. Ordinary priests likewise wear linen hats, reinforcing that every action performed at the altar or within the tabernacle must distinguish sacred from profane and clean from unclean while instructing the people in God's decrees. This external uniformity of white, blue, and gold on the head points to the deeper requirement that priests embody righteousness, grace, and divine wisdom in their service. With the change from the Levitical order to the eternal Melchizedek priesthood headed by Christ, these functions become spiritual, universal, royal, and uniformly righteous. Christ Himself demonstrated perfect submission by doing only the Father's will, offering His own life rather than animal substitutes. Those called under Him must therefore present their bodies as living sacrifices, devoting intellect, speech, relationships, and daily labor entirely to God. In the spiritual temple formed by the church, priests offer acceptable spiritual sacrifices by putting off sin, renewing the mind after Christ's humble pattern, and teaching holiness without syncretism from the surrounding world. Their service produces peace between God and worshipers, equips others for the same dedication, and continues eternally because the priesthood itself never passes away.

The function of priests centers on mediating between God and humanity by drawing near to Him in order to offer spiritual sacrifices and to bring reconciliation, understanding, and blessings back to the people. Under the new covenant the church constitutes a forming royal and holy priesthood whose members stand in this mediatorial position, first following their High Priest into God's presence and then leading others who will follow at a later time. Their primary responsibilities are to offer spiritual sacrifices acceptable to God through Jesus Christ and to show forth His praises both by private acts of worship and by public witness. These sacrifices include continual prayer, study and meditation on God's Word, thanksgiving expressed through the fruit of the lips, sharing encouragement and counsel, performing good works, and presenting one's own life as a living sacrifice. Such service requires daily discipline, the putting to death of sinful impulses, and the deliberate setting apart of time morning and evening so that God's Word is thoroughly considered and applied. Priests must maintain purity of conduct because only those cleansed internally by Christ's blood and kept pure by obedience to His Word can approach God acceptably. Their calling therefore obligates them to live every aspect of life as an act of worship, refusing to conform to the world while being transformed by the renewing of the mind. In this way the priesthood fulfills its mediatorial role, bridging God and the world until the entire human family is ultimately brought near.

The function of priests centers fundamentally on holiness, since serving as a bridge between God and His worshippers—instructing them, mediating for them, and helping bring them together—requires reflecting the very nature of the One they represent. From Melchizedek's early priesthood through the firstborn son's mediating role before Sinai, and culminating in Israel's calling to be a kingdom of priests, the priesthood's essential quality has always been holiness, since God repeatedly commands, "You shall be holy, for I am holy," a standard applied without distinction to rich or poor, priest or commoner, and carried forward unchanged into the New Covenant through Peter's epistle. This holiness is not mere ceremonial designation or moral behavior alone; it identifies God's very uniqueness and separateness from creation, an infinite majesty and perfect righteousness that overwhelms those who encounter it, as seen in Moses at the burning bush, Joshua before the Commander of the Lord's army, Isaiah's vision of the throne, and even the disciples before Christ's transfiguration and Peter's response to the miraculous catch of fish. Because the church itself is called "holy brethren" and identified as the temple of God, believers are called to attain this quality genuinely, not merely bear it as a positional title. Moses' glowing face after communing with God demonstrates that holiness can actually be transferred through intimate relationship with Him, encouraging believers that this same impartation is available to them through sustained fellowship, study, prayer, and obedience. The priesthood and Levites specifically bear responsibility for embodying and modeling this pursuit before the whole community. Through their instruction, their example, and the visible service conducted at the tabernacle and temple, they served as constant reminders that the entire nation—and later the entire church—is called to holiness, not merely to avoid sin. Their white linen garments, echoed in the "beauty of holiness" from the Psalms and the fine linen of the saints in Revelation, symbolize righteous acts performed in service to God, acts that stand believers in good stead for the resurrection. This holiness is inseparably tied to separation from worldliness, since believers as the temple of the living God cannot be unequally yoked with unbelief, and must cleanse themselves of all filthiness in pursuit of holiness perfected in the fear of God. It is also bound to love, gratitude, and grace: those who dwell on what God has already given become humble, resistant to false doctrine, and increasingly established in holiness through the Spirit. Ultimately, the priesthood's function points beyond ancient Israel's ministers to the present ministry and to every believer, since God's purpose is that all who are called become kings and priests under Christ, prepared through this present life to occupy that very position of holiness and service in His coming Kingdom.

Believers are a present royal priesthood offering spiritual sacrifices within the church, nourished by Christ's exclusive altar. The Feast of Tabernacles mirrors Levitical consecration, with its seven-day structure and blood application to ears, thumbs, and toes symbolizing hearing God, serving, and walking steadily. This pattern emphasizes present sanctification over merely prophetic future, inviting believers to be continually filled from God's table. Neglecting this spiritual food risks stagnation, so the feast serves as a vital period of consecation, strengthening believers to serve alongside their High Priest.

The function of the priesthood emerges from Peter's description of believers as "living stones" built into "a holy priesthood" and "a royal priesthood," called to offer spiritual sacrifices and to show forth God's praises. This calling is illuminated through Numbers 16-18, which establishes four qualifications for priestly service: God alone elects, never man; the priest belongs entirely to God rather than to himself or any earthly nation; he becomes holy in a specific, set-apart sense; and he alone has the exclusive prerogative to draw near to God. These qualifications reveal that holiness within Israel—and within the church—is not uniform, since God assigns distinct functions to distinct groups, as seen in the differing responsibilities given to the Levitical families of Kohath, Gershon, and Merari, with the priesthood itself restricted to Aaron's line. The rebellion of Korah, Dathan, and Abiram illustrates the seriousness of violating these appointed boundaries, since challenging God's chosen priesthood is treated as rebellion against God Himself. Three miracles—the earth swallowing the rebels, fire consuming the 250 censer-bearers, and the budding of Aaron's rod—vindicate God's choice of Aaron's priesthood beyond any human explanation. Central to priestly function is intercession: Aaron, taking fire and incense from the altar, ran into the plague-stricken congregation and "stood between the dead and the living," causing the plague to cease. This act mirrors the picture in Revelation 8, where incense symbolizes the prayers of the saints ascending before God, showing that intercessory prayer—for the world, the church, and fellow believers—is a defining priestly responsibility. Numbers 18 further clarifies priestly duty: Aaron and his sons must "bear the iniquity of the sanctuary" and of the priesthood itself, meaning they carry responsibility for its proper function. The Levites are given as a gift to assist them, yet strict boundaries remain—Levites may not touch the sacred vessels or altar, and any unauthorized person approaching the tabernacle is to be put to death. This gift-structure parallels Ephesians 4, where Christ gives the ministry as a gift to serve His church, just as the Levites were given to serve the priesthood. The overarching purpose of these detailed accounts is to establish how seriously God regards sanctification—the setting apart of persons, objects, and functions for His exclusive service. The priesthood's function, then, is not self-appointed or self-defined but divinely ordained, marked by exclusive access to God, guardianship of holy things, and the duty of intercession on behalf of the people. This foundation prepares the way for understanding Pentecost and the church's identity as a royal priesthood, called not to elect itself but to faithfully fulfill the specific service God has appointed.