2,715. Must an Oath of Judges Be in Hebrew?

Hilchos Shevuos 11:14

While the Geonim ruled that judges may impose an oath in any language that the one taking it understands, the Rambam says that his teachers only allowed an oath to be imposed in Hebrew; Rambam does not rule like his teachers. The practice has become to impose oaths in Hebrew, but the one taking the oath should have the subject of the oath explained to him until he understands the words of the oath; this is because an oath of judges is an oath of deposit, which must be understood. The practice has even become to impose an oath of enticement in Hebrew.

Hilchos Shevuos 11:15

One who must take an oath of judges for denying a definite claim, either under Biblical law or rabbinic law, is given a warning, which will be explained. One who must take an oath for a doubtful claim, either under Biblical law or rabbinic law, need not be given such a warning.