(3) باب سُنَّةِ الْعِيدَيْنِ لأَهْلِ الإِسْلاَمِ
Narrated Al-Bara':
I heard the Prophet (p.b.u.h) delivering a Khutba saying, "The first thing to be done on this day (first day of `Id ul Adha) is to pray; and after returning from the prayer we slaughter our sacrifices (in the name of Allah) and whoever does so, he acted according to our Sunna (traditions)."
Reference: Sahih al-Bukhari 951
In-book reference: Book 13, Hadith 3
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 2, Book 15, Hadith 71