What Galatians 3:20 really means: God Is One

God’s Direct Promise vs. the Mediated Law

Paul is reminding the Galatian believers that God’s original promise to Abraham came directly, without any middleman, because God alone made it by His own authority.

This matters because Paul is showing that the covenant of grace through faith - given long before the law - stands on a different, more direct foundation than the Mosaic Law, which was given through Moses as a mediator and even involved angels, as Acts 7:53 and Deuteronomy 33:2 suggest. Since a mediator is only needed when two parties must reach an agreement, the law’s mediation implies a distance between God and the people. But when God made His promise to Abraham, He did it one-sidedly, swearing by Himself - because He is one, and no third party was needed.

This highlights the personal, unchanging nature of God’s promise, setting the stage for Paul’s next point: if the promise came directly from the one true God, it cannot be canceled or added to by the law that came centuries later.

The One God and the One Promise

This verse addresses how God relates to us directly, personally, without anyone standing between Him and us, rather than abstract theology.

When Paul says, 'Now an intermediary implies more than one, but God is one,' he’s tapping into the heart of Israel’s faith: 'Hear, O Israel: The Lord our God, the Lord is one' (Deuteronomy 6:4). That oneness means God doesn’t need a middleman to keep a promise - He speaks, and it stands. The law, given through Moses and even angels (as in Acts 7:53), required a mediator because it involved two parties agreeing: God set the terms, and Israel said, 'We will obey.' But with Abraham, God alone passed between the pieces of the sacrifice (Genesis 15), showing it was all God’s doing from start to finish.

So the promise to Abraham wasn’t a contract needing negotiation - it was a declaration from the one true God, based on His own character, not human performance. This is why Paul stresses 'God is one': to show that grace flows directly from a single, unchanging source. Unlike the law, which came later and depended on human obedience through a mediator, the promise stands firm because it rests on God alone.

This sets up Paul’s next point: if the law came in centuries after the promise and required a mediator, it can’t undo or improve what God already swore to do by Himself. The promise stands on higher ground - because it was never a bargain, but a gift from the one God who keeps His word.

Salvation Without a Middleman

The heart of Galatians 3:20 is that salvation comes straight from God - not through rules, rituals, or religious go-betweens, but through faith in His promise.

Back then, many believed you needed priests, laws, or special mediators to be right with God. But Paul flips that idea by showing that God’s original promise to Abraham required no such thing - because 'God is one,' meaning He acts on His own authority and doesn’t need help to keep His word. This is good news: God came directly to Abraham and now comes to us through Jesus, fulfilling that promise.

So we don’t need to earn our way in or find someone to speak for us - because in Christ, the one true God has already spoken, and His promise stands firm.

The One Promise, the One Mediator, and the New Covenant

Paul’s point in Galatians 3:20 is not merely ancient history; it is the key to understanding how all Scripture holds together, from God’s oneness to Christ’s unique role as the one who connects us to God.

Jesus said, 'Hear, O Israel: The Lord our God, the Lord is one' (Mark 12:29), echoing the heart of Israel’s faith, and Paul builds on that truth - because if God is one, His promise flows from His singular, unchanging nature. The law came through mediators, as Acts 7:53 reminds us, but the promise to Abraham came directly from the one God. Now, in Christ, we see that while the law had many intermediaries, God has given us one final Mediator: 'For there is one God and one mediator between God and mankind, the man Christ Jesus' (1 Timothy 2:5).

This changes everything. The Abrahamic covenant was always meant to find its fulfillment in Christ, as Paul says in Galatians 3:16: 'The promises were spoken to Abraham and to his seed. The Scripture does not say 'and to seeds,' meaning many people, but 'and to your seed,' meaning one person, who is Christ.' The promise was not only for Abraham. It was fulfilled through him, pointing forward to Jesus. Unlike the old covenant, which needed priests and sacrifices and mediators, the new covenant 'is established on better promises' (Hebrews 8:6) and is secured by Christ Himself, who is both the Mediator and the sacrifice. Hebrews 9:15 calls Him the Mediator of that new covenant, not to add conditions, but to fulfill what God promised long ago - once and for all.

This means we don’t live by negotiating with God through rules or religious performance - we live by trusting the one promise from the one God, now fulfilled in the one Mediator. And when a church truly lives this out, it stops ranking people by how religious they seem and starts welcoming everyone through grace. When communities grasp that God didn’t wait for a mediator to make His promise, but acted freely in love, it frees them to show that same grace - no strings attached.

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