a mediator: one who stands between two parties to bring them together, settle their relationship, or guarantee it.
At its simplest the word names a go-between: someone who stands in the middle of two parties. It was a fairly ordinary term in the everyday Greek of the New Testament era, borrowed from the world of law and business, where a mediator was:
- the neutral arbiter who settled a dispute
- the trusted person who held money for both sides
- the guarantor who vouched for a debt
- the broker who arranged a deal
The concept of standing between God and people runs all through the Bible (Moses at Sinai, the priests, the prophets), but this particular word is not drawn from the Hebrew Scriptures. It appears only once in the Greek Old Testament, so the New Testament writers picked it up from the surrounding culture and put it to their own use.
That is why the word carries a different shade in each place it appears. Paul uses it of Moses, the go-between who received the law and handed it to Israel, and he draws a fine point from the very idea: a mediator implies two sides, so the law is a two-party arrangement, unlike the promise God gave directly to Abraham. In First Timothy the same word describes Jesus as the one mediator between God and the human race, the one who reconciles the two sides by giving his life as a ransom. In Hebrews it means something closer to a guarantor of a new and better covenant, one who does not merely pass the covenant along but puts it into force and secures it forever by his own death.
So across its six uses the word keeps one steady core (someone positioned between two parties to establish or secure their relationship) while the surrounding argument fills in what kind of go-between is meant, and who is standing between whom.
Nuances
What Paul means by the saying a mediator is not of one, but God is one (Galatians 3:20), and how it bears on the standing of the law. This is among the most contested verses in Paul, with hundreds of proposed readings since ancient times.
- majorityA mediator by definition presupposes two parties, so the law, given through a mediator, is a two-sided and conditional arrangement, inferior to the promise God gave directly and one-sidedly to Abraham.; J. B. Lightfoot, St Paul's Epistle to the Galatians (1865), on 3:19-20; F. F. Bruce, The Epistle to the Galatians (NIGTC, 1982); Richard N. Longenecker, Galatians (WBC, 1990)
- minorityThe angels are third-party cosmic powers and the law belongs to a lower order, so God was not straightforwardly its giver; the mediated law is thereby set over against the God who acts directly in Christ.; J. Louis Martyn, Galatians (Anchor Bible, 1997); Martinus C. de Boer, Galatians (NTL, 2011)
- minorityThe word one refers to the single unified family God intends (the one seed of 3:16, the one people of 3:28); Moses mediated only to Israel, so he is not mediator of that one family, which God unites through Christ.; N. T. Wright, The Climax of the Covenant (1991), ch. 7
Whether, in Hebrews 9:16-17, the writer briefly shifts the word for covenant to its everyday sense of a last will and testament (whose maker must die for it to take effect), or keeps the covenant sense throughout (with the death being the sacrificial victim that ratifies a covenant). The choice colors what kind of mediator Christ is.
- contestedThe writer plays on the double sense of the word, using its ordinary meaning of a will or testament, so that Christ's death activates the inheritance the way a testator's death does.; Harold W. Attridge, The Epistle to the Hebrews (Hermeneia, 1989); Craig R. Koester, Hebrews (Anchor Bible, 2001); F. F. Bruce, The Epistle to the Hebrews (NICNT, rev. ed. 1990)
- contestedThe word means covenant throughout; the death in view is the sacrificial victim that ratifies a covenant, as in the self-cursing oaths of the Old Testament, so Christ inaugurates and guarantees the covenant by his blood.; William L. Lane, Hebrews (WBC, 1991); Gareth Lee Cockerill, The Epistle to the Hebrews (NICNT, 2012); John J. Hughes, "Hebrews 9:15ff and Galatians 3:15ff: A Study in Covenant Practice and Procedure," Novum Testamentum 21 (1979): 27-96; Scott W. Hahn, "A Broken Covenant and the Curse of Death: A Study of Hebrews 9:15-22," Catholic Biblical Quarterly 66 (2004): 416-436