What are the three functions of every believer?

The moment we are saved we are given three assignments that define the rest of our lives: priesthood — our relationship to God, drawing near to Him through the Word and prayer; ambassadorship — our relationship to unbelievers, urging them to be reconciled to God; and ministry — our relationship to other believers, serving the Body of Christ through our spiritual gift. Priesthood defines the believer's relationship to God (1 Pet. 2:5–9). Every believer is a priest with the right to represent himself before the throne of grace (Heb. 4:16) and is called to live face-to-face with God. This private function is exercised through prayer (Heb. 13:15; 1 Thess. 5:17–19), the study of the Word, staying in fellowship (1 Cor. 11:28–32; 1 John 1:7–9), and growing in the grace and knowledge of the Lord (2 Pet. 3:18). Ambassadorship defines the believer's relationship to unbelievers (2 Cor. 5:17–20). Believers are appointed by Christ to the ministry of reconciliation and have a duty to the unsaved (Acts 1:8), urging men to be reconciled to God. As personal representatives of the Lord Jesus Christ, believers are to reflect Him by action and word (John 13:35; 17:23; 1 John 3:18). Ministry defines the believer's relationship to other believers (1 Cor. 12:7, 11; Rom. 12:1–8). Every believer is called to be a servant to every other Christian, using a sovereignly bestowed spiritual gift to build up and strengthen the Church. Believers are exhorted to concentrate on how to stimulate and encourage one another toward love and good deeds (Heb. 10:24–25).