It is a continual burnt offering
For the meat offering was burnt as well as the lambs, at least part of it:
which was ordained in Mount Sinai for a sweet savour, a sacrifice made
by fire unto the Lord;
that is, this law concerning the daily burnt offering was made on Mount Sinai, so long ago as the children of Israel were there; and it was then ordered that they should continually offer such a sacrifice by fire, which would be grateful and acceptable unto God, especially when done in faith of the sacrifice of his Son it was a type of; or which sacrifice was "made" F5 or offered at Mount Sinai, when the law of it was first given there: hence Aben Ezra observes, that this is a sign that they did not offer burnt offerings in the wilderness after they journeyed from Sinai; but then, though sacrifices were not so frequently offered by them as afterwards, yet one would think that the daily sacrifice would not be omitted, which seemed to be always necessary; nor would there be any, or but little use of the altar, and the fire continually burning on it, if this was the case; see ( Amos 5:25 ) .
F5 (hyveh) "quod obtulistis", V. L. "quod factum est", Pagninus; "quod sacrificatum fucrat", Piscator.