Who is Jesus the high priest of?

Jesus is the high priest of all people, not merely the Jews, because He is a high priest after the order of Melchizedek rather than Aaron. He is also called the high priest of good things to come, serving in a greater and more perfect tabernacle.

Les explains that Melchizedek was a high priest forever, not under the law or of the tribe of Levi, but a priest of all, covering the whole spectrum of the human race. Therefore Christ is not a high priest after the order of Aaron, but after the order of Melchizedek. That means He is not just the high priest of the Jew, but the high priest of whomever we might be. Hebrews 9:11 further says Christ became a high priest of good things to come by a greater and more perfect tabernacle, patterned after the heavenly one shown to Moses.

Why is Jesus not just the high priest of the Jews?

Christ is a high priest after the order of Melchizedek, not after Aaron. Melchizedek was not a priest under the Law or of the tribe of Levi, but a priest of all, covering the whole spectrum of the human race. Therefore Jesus is not merely the high priest of the Jew, but high priest of whomever we might be.