Purity is an institution whose effect is the elimination of mutual debts of two people against each other. The origin of Purity all over the world is wisdom, and for this reason, many of the effects and conditions of Purity are the same all over the world. Purity is one of the causes of falling obligation which has three types of coercion, contractual and judicial. Some have added a fourth type called rhetorical Purity. One of these types, because it is declared by the court, is called "judicial Purity", which is enshrined in Article 18 and Note 142 of the ICCPR. But despite its legal status, there are many differences among jurists about how to exercise judicial Purity. Some consider it to be absolutely pure and do not consider its design to be necessary to file a petition. However, in which case the lawsuit should be filed, no specific criteria have been set for it. It seems that in view of the clarification of the mentioned articles, the claim of Purity is in no way necessary to file a lawsuit; Because the claim of Purity in any case is accompanied by a kind of compound confession that causes a revolution in litigation. Therefore, its plan does not require a lawsuit and filing a lawsuit, and it is achieved only by defense, and the court is obliged to hear it.