وواعدنا موسى ثلاثين ليلة وأتممناها بعشر فتم ميقات ربه أربعين ليلة وقال (7:142) بالانجليزي

(7:142) And We appointed for Moses thirty nights, to which We added ten, whereby the term of forty nights set by his Lord was fulfilled. *99 And Moses said to Aaron, his brother: 'Take my place among my people, act righteously, and do not follow the path of those who create mischief.' *100

Tafseer Abu-al-A'la Maududi

Page 167 English Traditional

*99). After the exodus of the Israelites from Egypt which marks, on the one hand, the end of the constraints of slavery and on the other, the beginning of their life as an independent nation, Moses was summoned by God to Mount Sinai in order that he might receive the Law for Israel. He was initially summoned for a period of forty days so that he might single-mindedly devote himself to worshipping, fasting, meditation and reflection and thus develop the ability to receive the revelation which was to put a very heavy burden upon him.
In compliance with God's command, Moses left the Israelites at the place now known as the Wadi al-Shaykh which lies between Nabi Salih and Mount Sinai. The place where the Israelites had camped is presently called
Maydan al-Rahah. At one end of the valley is a hillock where, according to local tradition, the Prophet Salih pitched his tent after his migration from the land of Thamud. A mosque built as a monument to the Prophet Salih still adorns the landscape. Mount Harun is located at the other end of the valley where, again, according to local tradition, the Prophet Harun (Aaron) stayed after his exasperation with the Israelites because of their cow-worship. The top of the towering Mount Sinai, standing 7,359 feet high, is mostly enveloped by clouds. The cave to which Moses retired for forty days to devote himself to worship and meditation is situated at the top of the mountain, and still attracts many pilgrims. Close to the cave are a mosque and a church. Moreover, a monastery built in the Justinian period stands even today at the foot of the mountain. (See Tafhim al-Qur'an, al-Naml 27: nn. 9-10.)
*100). Although Aaron was senior to Moses in age by three years, he was placed under the direction of the Prophet Moses and was required to assist him in connection with his mission, As explained elsewhere in the Qur'an, Aaron was not assigned independent prophethood; he was rather appointed a Prophet by God in response to Moses' prayer that he be appointed as his assistant. (See Ta Ha 20: 29-31 - Ed.)