Spending the Night at Muzdalifah
Question :
What is the ruling on spending the night at Muzdalifah before midnight?
Answer:
It is Wajib (compulsory) upon the Hajj pilgrim to spend the night at Muzdalifah on the night before the 10th of Thul-Hijjah until the time of Al-Fajr, unless there is an excuse, such as illness or something similar. For such a person and whoever is responsible for his affairs, it is permissible for him to travel to Mina after the middle of the night. This is because the Prophet spent the night there (at Muzdalifah) during his Hajj until Fajr, and he allowed the people with excuses to leave from Muzdalifah to Mina after midnight.
Source:
Ash-Shaykh Ibn Baz
Fatawa Islamiyah, Vol. 4 Page 220