Exodus 29:25

And thou shalt receive them of their hands
After they had been put into them, and filled with them, and waved by them:

and burn them upon the altar for a burnt offering;
not the flesh of the ram, which is after ordered to be boiled and eaten by Aaron and his sons; but the fat of it, before described, with one loaf, one cake, and one wafer of unleavened bread, out of the basket: this was done

for a sweet savour before the Lord;
that it might be grateful and acceptable to him, as it was:

it is an offering made by fire unto the Lord;
(See Gill on Exodus 29:18).