The Prayer of the Two Eids
Man Lā Yaḥḍuruh al-Faqīh|Volume 1|Book 1|Chapter 79
عَنْ زُرَارَةَ عَنْ أَبِي جَعْفَرٍ عَلَيْهِ اَلسَّلاَمُ قَالَ: «صَلاَةُ اَلْعِيدَيْنِ مَعَ اَلْإِمَامِ سُنَّةٌ وَ لَيْسَ قَبْلَهُمَا وَ لاَ بَعْدَهُمَا صَلاَةٌ ذَلِكَ اَلْيَوْمَ إِلَى اَلزَّوَالِ.
From Zurarah, from Imam Muhammad ibn Ali Al-Baqir عليه السلام who said: "The prayer of the two Eids (Eid al-Fitr and Eid al-Adha) with the Imam is a Sunnah, and there is no prayer before or after them on that day until noon (zawal)."
- Ṣaḥīḥ al-Faqīh, p. 71