Then, a few weeks ago, I had to preach on it. I came to God’s righteousness having just spent a lot of time in Isaiah 40-66 (for the THINK conference), and Deuteronomy (for a book on it), both of which shaped the way I approached the subject. So what does it mean to speak of God’s righteousness, or to say that God is righteous? Here’s what I said.

Imagine a Venn diagram with three major circles, arranged in a triangle so that all three overlap in the middle. The word righteousness is in the centre, where three other Bible words overlap together: uprightness, justice, and salvation. Each of those three words are frequently paired with righteousness in the Old Testament, as if their meanings “rhyme” with it.

Start with uprightness. “Shout for joy in the LORD, O you righteous! Praise befits the upright” (Ps 33:1). So righteousness overlaps closely with the idea that God is upright, and so should his people be. Righteousness in this sense is to be correctly positioned relative to reality. It involves being right as opposed to wrong - theologians would call it conformity to an external norm - but it also means standing straight rather than wonky. If you have an upright glass, that means a glass that doesn’t spill. If you have an upright building, that means a building that doesn’t subside, give way, or crumble. The righteous, the upright, are those who stand properly and correctly in proportion to reality, and they don’t crumble, and they don’t give way. They are in the right. That’s one element.

Another word that overlaps with righteousness in the Bible is justice. We would probably naturally realize that justice and righteousness are paired together: “Give the king your justice, O God, and your righteousness to the royal son!” (Ps 72:1). In Scripture, the concept of justice has to do with giving people their due: giving people that which they are entitled to, and making judgments on the basis of the merits of their case, not on our prejudices, preferences or incentives. If you are just in the Bible, it means you’re not judging for a bribe, or because you don’t like the person, or because you’ve pre-decided the outcome, but because they merit or warrant this particular judgment. That closely overlaps with the biblical category of righteousness too.

The third category that overlaps with righteousness, especially in Isaiah, is salvation: “He has clothed me with garments of salvation; he has covered me with the robe of righteousness” (Is 61:10). This is the most surprising of the three. You don’t normally think of righteousness in terms of rescue. So why is the righteousness of God connected with his salvation of his people? Because God has made a covenant with his people, in which he has promised to deliver them. Which means that for God to be righteous means for him to follow through on his promises to save, in faithfulness to his covenant. God’s righteousness means that he must save his people because he said he would. If he didn’t, he would break his covenant and dishonour his name.

When you get those three ideas together - uprightness, justice and salvation - and they all overlap in the middle of the Venn diagram, that’s what righteousness is. To say that God is righteous is to say that he is upright and correct in all of his ways, just and impartial in all of his judgments, and committed to save his people in accordance with the covenant he’s made with them. That’s what we mean when we say God is righteous.