Hadith -- Bakr Eid

Narrated 'Abdullah bin 'Amr bin Al-'As (Radi-Allahu 'anhu):

I witnessed the Prophet (Sallallahu 'Alaihi Wa Sallam) when he was
delivering the sermon on the Day of Nahr. A man stood up and said, "I
thought that such and such was to be done before such and such. I got my
hair shaved before slaughtering." (Another said), "I slaughtered the Hadi
before doing the Rami." So, the people asked about many similar things. The
Prophet (Sallallahu 'Alaihi Wa Sallam) said, "Do it (now) and there is no
harm in all these cases." Whenever the Prophet (Sallallahu 'Alaihi Wa
Sallam) was asked about anything on that day, he replied, "Do it (now) and
there is no harm in it."

Bukhari Vol. 2 : No. 793