Rashi on Leviticus 17:5/רש"י על ויקרא י״ז:ה׳

1אשר הם זבחים [THAT THE CHILDREN OF ISRAEL MAY BRING THEIR SACRIFICES] WHICH THEY SACRIFICE [IN THE OPEN FIELD ….. UNTO THE LORD] — "which they sacrifice" means, which they are at present accustomed to sacrifice.