Hebrews 8:3-5 For every high priest is ordained to offer gifts and sacrifices: wherefore it is of necessity that this man have somewhat also to offer. For if he were on earth, he should not be a priest, seeing that there are priests that offer gifts according to the law: Who serve unto the example and shadow of heavenly things, as Moses was admonished of God when he was about to make the tabernacle: for, See, said he, that thou make all things according to the pattern showed to thee in the mount. 

‘Ordained’ [Greek: kathistemi] Translated “ordain” (5:1; 8:3; Tit. 1:5); “appoint” (Acts 6:3); “conduct” (Acts 17:15); “set” (2:7); “make ruler” (Matt. 24:45-47; 25:21-23; Luke 12:42-44); and “make” (7:28; Luke 12:14; Acts 7:10, 27, 35; Rom. 5:19; 2Pet. 1:8).

‘Offer gifts and sacrifices’ Two kinds of offerings: Gifts to God acknowledging His government and providence in the universe. Sacrifices to God acknowledging sin and the necessity of atonement.

‘Wherefore it is of necessity that this man have somewhat also to offer.’ Since all priests needed to make offerings, it was required of Christ to make one (10:1-12).

‘For if he were on earth, he should not be a priest, seeing that there are priests that offer gifts according to the law.’ The Levites were still carrying on the temple service in Jerusalem, thus was it not possible, therefore, for Christ to perform the office of a priest, being of the tribe of Judah, to which tribe the priesthood did not belong. The Levites served in this worship of shadows of heavenly things (8:4-5).  During Christ’s earthly ministry as well as for many years before, the priests and Pharisees were not serving God, but themselves, hence His judgement of them (Matt. 23).

‘See, said he, that thou make all things according to the pattern showed to thee in the mount.’ Quoted from Exodus 25:9, 40. Moses had a literal model to go by (Ex. 25:9, 40; cp. Heb. 8:5; 9:23). David later saw a model of the temple (1Chron. 28:11-19).

‘Pattern’ [Greek: tupos] translated as example (Php. 3:17; 1Cor. 10:6, 11; 1Thess. 1:7; 2Thess. 3:9; 1Tim. 4:12; 1Pet. 5:3); pattern (Tit. 2:7; Heb. 8:5); manner (Acts 23:25); fashion (Acts 7:44); form (Rom. 6:17); figure (Acts 7:43; Rom. 5:14); and print (John 20:25).