The passage also grounds the claim in a concrete fact about Jesus: “our Lord” comes from Judah, and Moses did not assign Judah to priestly altar service. That mismatch is presented as public, obvious evidence that the priesthood now being discussed does not fit the older Levitical category (Hebrews 7:13–14).

Where interpretation differs (only where needed)

1) What “perfection” means (v. 11). Some understand it mainly as full access to God and a cleansed conscience—what the temple system pointed toward but could not complete. Others take it more broadly as the intended completion of God’s purposes for worship and covenant life. In both cases, the argument’s force is the same: the earlier priesthood was not the final answer.

2) How broad “law” is in v. 12. Some read “law” here as focused on priestly regulations tied to lineage and temple service. Others read it as indicating a wider change in the Mosaic arrangement as a whole. The immediate support in vv. 13–14 stresses lineage/tribal rules, but the author’s wording is broad enough that readers debate how far the change reaches.

Why the disagreement exists

The passage connects “law” to priesthood, then immediately proves the point by tribal ancestry (Judah vs. Levi). That pushes readers toward a narrower “priestly-law” sense. Yet the author also frames the Levitical priesthood as the setting “under” which the people received the law (v. 11), which can sound like a larger, whole-system claim. The text itself supplies both signals.

What this passage clearly contributes

• Explicit claim: Scripture’s talk of “another” priest in Melchizedek’s pattern shows the Levitical/Aaronic priesthood was not the endpoint.
• Explicit claim: a changed priesthood entails a changed “law” connected to it.
• Explicit claim: Jesus’ Judah ancestry conflicts with the Mosaic priestly assignment, so his priesthood must be different in kind.
• Theological inference (from these claims): the author sees Jesus’ priesthood as authorized by Scripture in a way that reconfigures how God’s people relate to priesthood, worship, and the Mosaic framework connected to Levitical service.

no one (oudeis)