Zevachim 56 - The Area for Slaughter, the Time for Blood
Most holy offerings must be eaten, and the peace offerings must be slaughtered "in front of the Tent of the Meeting." In order to make the whole area of the Courtyard "in front," there were additional doors, on the opposite far sides of the Hall, leading into the Hall.
The blood of the sacrifices had to be offered before sunset. After sunset it became disqualified, because of the verse "on the day that he offers his sacrifice it shall be eaten." This teaches that both the slaughter and the offering of the blood must occur on the same day.
Art: Charles Théodore Frère - Sunset On The Nile
