Chapter on the Obligations of Hajj
Man Lā Yaḥḍuruh al-Faqīh|Volume 2|Book 3|Chapter 48
وَ قَالَ اَلصَّادِقُ عَلَيْهِ اَلسَّلاَمُ: «وَ اَلْوُقُوفُ بِعَرَفَةَ سُنَّةٌ وَ بِالْمَشْعَرِ فَرِيضَةٌ وَ مَا سِوَى ذَلِكَ مِنَ اَلْمَنَاسِكِ سُنَّةٌ.
Imam Jafar ibn Muhammad Al-Sadiq عليه السلام said: "Standing at Arafah is a Sunnah, and standing at al-Mash'ar is an obligation, and everything else from the rituals is Sunnah."
- Ṣaḥīḥ al-Faqīh