In the New Testament, the Epistle to the Hebrews is unique in designating Jesus as High Priest. The author of Hebrews gives a clear and definite teaching regarding the priesthood of Christ. That Jesus Christ is our High Priest belongs to the «main point of the things being said» (8,1). The use of the messianic oracle of Ps 110, 4 and its explanations are key to the teaching about how Christ became High Priest and the significance and meaning of Christ becoming High Priest/Priest according to the order of Melchizedek. This study is an attempt to explore Hebrews' teaching about the priesthood of Christ in Heb 5,1-7,28 and the role of Ps 110,4 in it. Heb 5,1-7,28 is an embedded discourse with its own internal organisation: with an introduction, paragraphs developing the theme and a conclusion.