Galatians 3:20

Analysis & Commentary

Now a mediator is not a mediator of one, but God is one. This dense, cryptic verse has sparked much debate. 'A mediator is not a mediator of one' (ho de mesitēs henos ouk estin, ὁ δὲ μεσίτης ἑνὸς οὐκ ἔστιν)—a mediator (mesitēs, μεσίτης) by definition implies two parties in negotiation or contract. Moses mediated between God and Israel at Sinai—a bilateral covenant requiring mutual obligations. Israel had to obey; God would bless. This required a mediator to broker the two-party agreement.

The contrasting statement: 'but God is one' (ho de theos heis estin, ὁ δὲ θεὸς εἷς ἐστιν). The promise (epangelia, ἐπαγγελία) to Abraham was unilateral—God alone swore the oath (Genesis 15:17, 22:16-18), requiring nothing from Abraham. No mediator was needed because the promise was God's unconditional commitment. The phrase 'God is one' could also echo the Shema (Deuteronomy 6:4)—God's unity and singularity means He acts alone in the promise-covenant, unlike the Law-covenant that required mediation between two parties.

Paul's point: the Law's bilateral, mediated nature proves its inferiority to the promise's unilateral, unmediated nature. The promise depends solely on God's faithfulness; the Law depends on human obedience—and humans fail. Therefore, the promise-gospel is superior to the Law-system. God's unilateral, gracious promise cannot be overthrown by the Law's conditional, bilateral demands.

Historical Context

Mediation language pervades the Mosaic covenant—Moses stood between God and Israel, conveying God's words and Israel's responses (Exodus 19:7-9, 20:18-21, Deuteronomy 5:5). The Law was a suzerainty treaty: God (suzerain) and Israel (vassal) entered a covenant with mutual obligations. By contrast, the Abrahamic covenant (Genesis 15:7-21) was unilateral—God alone passed between the sacrifice pieces, binding Himself by oath without requiring Abraham's performance. Hebrews 8-9 develops this: Christ mediates a better covenant based on better promises, superseding the Mosaic covenant.

Questions for Reflection

• How does the bilateral nature of the Law-covenant (requiring a mediator between God and Israel) differ from the unilateral nature of the Abrahamic promise?
• What does the phrase 'God is one' reveal about the Abrahamic promise depending solely on God's faithfulness rather than human performance?
• Why is a unilateral, unmediated promise-gospel superior to a bilateral, mediated Law-covenant? How does this give you assurance of salvation?