Because priesthood existed for the purpose of offering sacrifices, Jesus is regarded as a priest because he has offered a sacrifice (himself) once for all. This has rendered the OT sacrifice system obsolete, together with the Temple priesthood. The OT model for Christ's high priesthood is that of the priest‐king Melchizedek (Heb. 7: 26).
Citation for priesthood of Christ
Citation styles are based on the Chicago Manual of Style, 15th Ed., and the MLA Style Manual, 2nd Ed..
MLA
"priesthood of Christ." In A Dictionary of the Bible. Ed. W. R. F. Browning. Oxford Biblical Studies Online. May 25, 2013. <http://www.oxfordbiblicalcstudies.com/article/opr/t94/e1523>.
Chicago
"priesthood of Christ." In A Dictionary of the Bible. , edited by W. R. F. Browning. Oxford Biblical Studies Online, http://www.oxfordbiblicalcstudies.com/article/opr/t94/e1523 (accessed May 25, 2013).