dating the surah al-layl

the verses and the sūrahs of the qur an were gradually revealed to the prophet muhammad (pbuh) during the 23 years in mecca and medina. information of the time, place, and amount of descendants and verses - especially in cases of conflict - are of the requirements of the quranic researches. sūrah al-layl is one of the disputed sūrahs, that in order to achieve the goal, we have to use two types of extra and intra-textual evidences. from this point of view, the present research, in a descriptive-analytical method, seeks to answer the question “how is the dating of sūrah al-layl based on the extra and intra-textual evidences?” the findings indicated that the extra-textual evidences included: 1- traditions of the order of descend, 2- traditions of the cause of revelation, 3- exegetes’ views. among these indications, the traditions of the cause of revelation tended to be criticized. but the other two extra-textual evidences, as well as intra-textual ones, which were received with deep attention of the verses of the sūrah, proved this sūrah to be makkī, and based on the totality of the evidences, its descent dates back to about the first year of the prophet’s (pbuh) mission, at his secret invitation.