Rashi on Exodus 34:26/רש"י על שמות ל״ד:כ״ו

1ראשית בכורי אדמתך THE FIRST OF THE FIRST-FRUITS OF THY GROUND [THOU SHALT BRING INTO THE HOUSE OF THE LORD THY GOD] — but only from the seven kinds of produce which are mentioned as an excellency of thy land (Deuteronomy 8:8) “a land of wheat and barley and vines etc (Mishnah Bikkurim 1:3). The דבש mentioned in this verse is date honey (not that of bees).

2לא תבשל גדי THOU SHALT NOT SEETHE A KID [IN ITS MOTHER’S MILK] — This is a prohibition to mix meat with milk. This is written three times in the Torah: once to prohibit the eating of such mixture, once to prohibit us from deriving any other benefit (besides eating) from it and once to prohibit the cooking of it (Chullin 115b; cf. Rashi on Exodus 23:19).

3גדי A KID — Any tender young animal is comprehended under the term גדי, a calf and a lamb also. From the fact that the writer felt it necessary to state specifically in several passages “a kid of the goat” you may learn that the term גדי without further definition implies any suckling (young animal) (Chullin 113a; cf. Rashi on Exodus 23:19).

4בחלב אמו IN THE MOTHER’S MILK — A fowl is therefore really excluded from this law since it has no milk; for the prohibition regarding it (using it with milk) is not a Biblical law but only an enactment of the Soferim (Chullin 113a).