#Exodus 20:16

The eighth commandment

You shall not bear false witness.

Despite nearly two millennia of interpretation, this commandment isn’t just some fancy biblical language for the broad category of “lying.” It actually is about what it says: being a witness. In court.

You can’t violate this commandment in private. Witnessing was a public act. (Remembering that witnessing here means saying something, not seeing something.) It’s not regular old lying or deceit - there’s a different Hebrew word for that, and there’s no biblical law against it.

This is, simply, a law against perjury. Why would such a thing be in the Ten Commandments? Seems awfully specific (which is why, I think, everyone from Origen and Augustine on wanted to expand the meaning). But there are multiple biblical laws about testimony, for good reason.

Witnesses were the main, almost exclusive, form of evidence. False witnesses, or conspiring witnesses, could (and still can) ruin a defendant’s life. Just ask poor Naboth. Reliable witness was the underpinning of the entire justice system, as is still largely the case.

This is why just about the most solemn ritual moment in our civic lives is being sworn in under oath in court. It’s two commandments in one: don’t bear false witness and don’t take an oath in vain. Truthfulness, in that specific context, is more important than anywhere else.

So we’re not content with simply having laws against perjury and penalties for committing it, like we do with every other crime. We invest it with this symbolic significance that is supposed to invoke a higher ethics, a potential divine involvement, etc.

All of which is to say there’s actually nothing “narrow” about this commandment just being about perjury, not about lying more generally. Perjury is still a big deal, still with a religious component, almost uniquely in modern civics. And it was even more so back then.