Jundab bin Sufyan reported: I was with Allah's Messenger ( صلی اللہ علیہ وسلم ) on the day of 'Id al-Adha. While he had not returned after having offered (the Id prayer) and finished it, he saw the flesh of the sacrificial animals which had been slaughtered before he had completed the prayer. Thereupon he (the Holy Prophet) said: One who slaughtered his sacrificial animal before his prayer or our prayer ('Id), he should slaughter another one in its stead, and he who did not slaughter, he should slaughter by reciting the name of Allah.

Jundab bin Sufyan reported: I was with Allah's Messenger ( صلی اللہ علیہ وسلم ) (on the occasion) of 'Id al-Adha. After he had completed the prayer with people, he found that the goats had been slaughtered, whereupon he said: He who slaughtered sacrificial animal before the prayer should slaughter a goat (again) in its stead and he who has not slaughtered he should slaughter it by reciting the name of Allah.

This hadith has been narrated on the authority of al-Aswad bin Qais with the same chain of transmitters.

Jundab al-Bajali reported: I saw Allah's Messenger ( صلی اللہ علیہ وسلم ) observing ('Id) prayer on the Day of Sacrifice (10th of Dhu'l-Hijja) and then delivering a sermon and he said: He who sacrificed the (animal) before offering ('Id) prayer, he should offer again in its stead, and he who did not sacrifice the animal should slaughter it by reciting the name of Allah.

A hadith like this has been narrated on the authority of A'mash with the same chain of transmitters.