Here the subject is: the difference it makes when our lives are lived just to please the Lord.
The idea of priesthood in the Bible cannot be over-emphasized, for four reasons at least. First, because the priesthood was the divine solution to provide a bridge between sinful Israelites and a holy God. Second, because the priests and the sacrifices they offered would be God’s picture book to illustrate the perfect Sacrifice made at Calvary for the whole world. Third, some great lessons can be learned from these chapters because all believers today are called “a holy priesthood” and “a royal priesthood” (1 Pet 2:5, 9), although our priesthood is significantly different from theirs. Fourth, the greatest human who ever lived, the incarnate Son of God, is a Great High Priest whose ministry is eternal. Concerning this, the Father addressed His Son: “You are a priest forever according to the order of Melchizedek” (Ps 110:4; Heb 5:6). In other words, those of us who trust in Christ will be forever dependent on His high priestly ministry. So these are good reasons to pay close attention to Leviticus 21 and 22, where the subject is the priests’ sanctification and sacrifices. The emphasis is on how sanctification (being set apart for God’s use) is practically applied. The theme occurs six times in this section: “I the Lord, who sanctify you, am holy” (21:8; see also 21:15, 23; 22:9, 16, 32). The first two paragraphs deal with sad and happy times—how priests should comport themselves regarding family funerals and marriages. While our instructions are different, yet God’s servants in this age are told, “I do not want you to…sorrow as others who have no hope” (1 Thess 4:13), and “Do not be unequally yoked together with unbelievers” (2 Cor 6:14). Yes, people should see the difference that Christ makes in every believer’s life.