From here, it is understood that Allah, the Just and Merciful, has not granted the possibility of attaining certainty about Islamic beliefs and deeds, and of achieving unity in the religion, only to the companions of His Prophet; rather, He has bestowed it upon all Muslims until the Day of Judgment, so that no generation of them would have any argument against Him or be able to offer the excuse: “Had we met the Prophet, we would have attained certainty about our beliefs and deeds and would not have differed among ourselves”; as Allah Almighty has said: ﴿وَأَقْسَمُوا بِاللَّهِ جَهْدَ أَيْمَانِهِمْ لَئِنْ جَاءَهُمْ نَذِيرٌ لَيَكُونُنَّ أَهْدَى مِنْ إِحْدَى الْأُمَمِ ۖ فَلَمَّا جَاءَهُمْ نَذِيرٌ مَا زَادَهُمْ إِلَّا نُفُورًا﴾[1]; “And they swore by Allah with their strongest oaths that if a warner had come to them, they would surely have been more guided than all the nations; but when a warner did come to them, it increased them in nothing except aversion.” Similarly, those who met the Prophet did not attain certainty about their beliefs and deeds and differed among themselves, just like these people, so that the first and the last of this nation would be equal. In any case, Allah’s justice requires that He provide later generations with all the necessary means for attaining certainty that He provided for the first generation, so that all are equal in this regard and their superiority over one another becomes clear; as He has said: ﴿إِنَّمَا أَنْتَ مُنْذِرٌ ۖ وَلِكُلِّ قَوْمٍ هَادٍ﴾[2]; “You are only a warner, and there is a guide for every people.” This means that in every generation of Muslims, there exists a living guide whom Allah has appointed and about whom His Prophet has informed; accordingly, his statements and actions reveal those of Allah and His Prophet. It is the duty of every Muslim to know this guide through explicit statement or sign, and to refer to him alongside the Book of Allah. Therefore, a belief or deed that is not based on this is not accepted, even if it is based on narrations—except for narrations that are mutawatir, as they rationally lead to certainty, and certainty can be the basis for a Muslim’s belief and deed; or narrations that are transmitted from a living guide to the Muslims in his time, so long as those Muslims are not at fault in failing to access him—given that narrations from a living guide, whenever they are contrary to reality, are typically identified and corrected by him, since attributing lies to the living is not easy and can be easily identified and corrected by them—unlike narrations from past guides, who are not able to identify and correct them.