Abstract Judicial Oath, whether requested by the defendant or plaintiff, plays a vital role in establishing or denying the right, for the purposes of resolving disputes between people, especially when the right holder is unable to prove his right. Therfore, this paper sheds light on the plaintiff?s oath in the cases pending before the Jordanian Sharia courts, and examines the nature of the Judicial Oath and its main types and conditions. Furthermore, this paper explores the effect of such oath under the Islamic jurisprudence and the effect of refusal to swear any oath. Throughout this paper, it is argued that tendering the oath is allowed in personal status matters, so that neglecting the oath and rejecting it is tantamount to acknowledgment by the defendant of the right claimed. It is also concluded that the party to whom the oath is tendered and who has refused it without tendering it back to the other party and the other party to whom the oath has been tendered back and who has refused to take it, will lose his case. This is why oath may in some circumstances be a critical element in winning the case.