He shall kill it on the side of the altar, northward before the Lord. In the sacrifice of the bullock it is only "before the Lord" (Leviticus 1:5). No doubt the same place is meant in both cases, but it is specified with more exactness here.
On the western side of the altar was the tabernacle, on the east side the heap of ashes (Leviticus 1:16), on the south side probably the ascent to the altar (see Josephus, 'De Bell. Jud.,' Leviticus 5:5, Leviticus 5:6); on the north side, therefore, was the most convenient slaughtering place, and this is probably the reason for the injunction.