God has promised reward to the believers and the righteous, and threatened punishment to the disbelievers and wrongdoers. One of the wise divine methods for distinguishing believers and the righteous from disbelievers and wrongdoers is the testimony of exalted witnesses from every nation and community regarding their good and evil deeds. Prophets, their successors, and the Imams (peace be upon them) are the most prominent and evident examples of such witnesses to deeds. Human actions have two aspects: external and internal. Intention, motive, and purpose in performing a good or bad act play a crucial role in determining its value, lack of value, or anti-value, and consequently the degree of reward or punishment. Therefore, the witnesses to deeds on the Day of Resurrection, in addition to being aware of the apparent aspects of individuals’ actions, are also aware of their inner and hidden dimensions. Thus, they possess knowledge of the unseen aspect of the deeds of those upon whom they testify. Undoubtedly, they enjoy a special existential capacity that enables them to attain such extensive knowledge. This criterion also applies to their awareness of other unseen realities of the world. Hence, the scope of the knowledge of these witnesses to deeds is extremely vast and profound.