The belief in the appearance of a savior who will fill the world with justice and equity and establish a global government is one of the fundamental beliefs of all religions, especially Muslims, both Sunni and Shia. Therefore, all are awaiting that savior and grand reformer. In fact, the seed of expectation was planted after Adam's (AS) exit from paradise, so that there would be "the expectation of returning to paradise under the leadership of a heavenly guide who would be man's leader in the struggle against Satan." In the struggle of the prophets against Satan and his hosts, who block the attainment of paradise, "the second seed of expectation was also planted, the expectation of the sovereignty of Allah and the defeat of Iblis and its manifestations." In this regard, we referred to the Nadbah Supplication and searched for the symbols of truth and falsehood in it, and the hardships that the divine prophets, the Holy Prophet (PBUH), and the Master of the Pious endured for the sovereignty of truth against the front of falsehood. Also, in a section of the article, constructive expectation and negative expectation are discussed, and constructive expectation from the viewpoint of verses, traditions, and the Nadbah Supplication is briefly examined, proving that real expectation is hopeful, life-giving, constructive, and falsehood-destroying. The introduction of various types of negative expectation and the Infallible Imams' combat against this type of expectation have also been examined. In reviewing the discussion of expectation in other religions, we concluded that almost all living religions of the world are somehow aligned with the principle of expectation. In the final part of the article, the duties of the awaiters of Imam Mahdi (AJ) from the perspective of the Nadbah Supplication and traditions were listed, stating that a real awaiter must engage in self-building and refinement, observe the rights of his brethren, be a person of struggle and jihad, and most importantly, gain cognizance of his Imam and follow him.