Shevuot שבועות

An oath in Jewish law is not an ornament of speech but an act with consequences. The tractate divides oaths into kinds: an oath about the future and about the past, a vain oath, the oath of a witness who refuses to testify, the oath of one who denies a debt.

The most important are the judicial oaths: where proof is lacking, the court does not decide at random but requires one of the parties to swear—and with that the case ends. From here too comes the gravity with which Jewish law regards uttering the Name in vain.

Order: Nezikin. There is Gemara in both the Babylonian and the Jerusalem Talmud.