Nasai

Urdu Hashiyah (Commentary):

"O Thubayr! Become illuminated." Thubayr is the name of a mountain which is located within the boundaries of Muzdalifah. It is evident that when the sun rises, its light first falls upon the mountain. From the mountain becoming illuminated, one can discern that the sun has risen. The intention of the people of Jahiliyyah was that when the mountain becomes illuminated, i.e., when the sun rises, then they would proceed. However, the Messenger of Allah (sallallahu alayhi wa sallam) set out before the sun had risen, and this is the Sunnah. Although, if the sun rises while one is still in Muzdalifah, it does not harm the Hajj, because in the crowd it is possible for this to happen.

Hadith Commentary:
Thabir is the name of a mountain in Muzdalifah, which lies to the left when coming towards Mina.
Hafiz Ibn Kathir states: "It is a well-known mountain there, and it is on the left of the one going to Mina. It is the greatest of the mountains of Makkah. A mountain of the tribe of Hudhayl is known by it; a man named Thabir from Hudhayl was buried in it."
That is, Thabir is a great mountain of Makkah, which lies to the left when going to Mina, and it is famous by the name of a man from Hudhayl named Thabir, who was buried there.
It is Sunnah to depart from Muzdalifah for Mina before sunrise.
In Sahih Muslim, the hadith of Jabir (radi Allahu anhu) gives further detail as follows:
"Then he (sallallahu alayhi wa sallam) mounted al-Qaswa (his she-camel) until he came to al-Mash'ar al-Haram. There, he faced the qiblah, supplicated to Allah, magnified Him, proclaimed His oneness, and continued standing until the light became very clear. Then he departed before the sun had risen."
That is, when returning from Arafat, the Prophet (sallallahu alayhi wa sallam) mounted his she-camel al-Qaswa, came to al-Mash'ar al-Haram in Muzdalifah, and there, facing the qiblah, he recited takbir and tahlil, and remained there until it became very bright, but before the sun rose, he (sallallahu alayhi wa sallam) departed from there.
In the era of ignorance (Jahiliyyah), the people of Makkah used to depart from there after sunrise; in Islam, it was established to depart before sunrise.

Hadith Commentary:
(1)
Thabir is a very large mountain in Muzdalifah, which lies to the right when going towards Arafat and to the left when going towards Mina. This mountain became famous by the name of a man from the tribe of Hudhayl who is buried there, and his name was Thabir.

(2)
From this hadith, it is established that one should depart from Muzdalifah towards Mina before sunrise. The detail of this is found in Sahih Muslim, where it is mentioned that the Messenger of Allah (sallallahu alayhi wa sallam) rode his she-camel Qaswa’ when returning from Arafat until he reached the Sacred Monument (al-Mash‘ar al-Haram) in Muzdalifah. There, facing the qiblah, he engaged in takbir and tahlil, and remained there until it became quite bright. Then, before sunrise, he departed from there towards Mina. (Sahih Muslim, al-Hajj, Hadith: 2950(1218))
Whereas, in the era of ignorance, the practice of the polytheists was contrary to this. They would depart from there after sunrise.
Regarding the standing at Muzdalifah, the statement of Allah, the Exalted, is:
﴿فَإِذَا أَفَضْتُم مِّنْ عَرَفَاتٍ فَاذْكُرُوا اللَّـهَ عِندَ الْمَشْعَرِ الْحَرَامِ ۖ وَاذْكُرُوهُ كَمَا هَدَاكُمْ﴾ (al-Baqarah: 198: 2)
“Then when you depart from Arafat, remember Allah at the Sacred Monument, and remember Him as He has guided you.”
(3)
Wherever one finds a place in Muzdalifah, one should perform the standing (wuquf) there, but one should not stay in the Valley of Muhassir.

1938. Commentary: The actual time for departure from Muzdalifah is after the Fajr prayer and before sunrise. There is an exemption only for the weak, that they may leave after midnight.

625 Lexical Explanation:
«لا يفضون» would not return, meaning from Muzdalifah towards Mina.
«اشرق» is in the imperative form from «اشراق». «اشراق» means to enter into light, i.e., it is required that the sun should rise upon you.
«ثبير» — the "tha" has a fatha and the "ba" has a kasrah beneath it. Due to being the object of a suppressed vocative, it is mabni ‘ala ad-damm. It is the name of a well-known and famous mountain that comes on the left side of one going towards Mina. It is counted among the great mountains of Makkah. It became known by the name of a person from the tribe of Hudhayl named Thabir. He was buried on this mountain. There is also another narration regarding this. «كيما نغير» means: so that we may walk and our horses may carry us at full gallop. [سنن ابن ماجه ، المناسك ، باب الوقف لجمع ، حديث : 3022 ]

Benefit: From this hadith, the evidence is derived that the return from Muzdalifah should be in the light before sunrise, and whoever was not able to remain there until sunrise, his standing (wuquf) has been missed.