Wyjścia 34:19 Komentarz: Rashi, Chizkuni, Sforno & Rashbam

כל פטר רחם לי EVERY FIRST OFFSPRING OF THE WOMB IS MINE amongst human beings,

כל פטר רחם לי, “the first fruit of the womb belongs to Me.” Earlier, this expression had included every domestic animal, now each species of animal has been named separately to show to which species this law applies.

כל פטר רחם לי, the commandment applies to male humans and male new born animals of the categories that are domesticated and fit to eat for Jews. Seeing that one category of “unclean” animal, the donkey, is also part of this legislation, though, of course such an animal is not fit to be sacrificed on the altar of the Temple, the Torah has to add certain qualifications when writing about this commandment. Whereas the “pure” firstborn may not be redeemed and made secular, but must themselves be offered on the altar, their blood and fat remaining there, the donkey either has to be redeemed or to be killed in a manner that precludes its flesh being used commercially. [it may not be consumed seeing it is an “unclean” animal. Ed.] (Numbers 18,17)

וכל מקנך וגו׳ AND also ALL THY CATTLE WHICH IT (the mother animal) BRINGS FORTH AS MALE BY AN OX OR AN ASS OPENING its womb: it means, that a male animal opens her womb.

פטר is an expression denoting “opening”; similar is (Proverbs 17:14) “As if one openeth (letteth run) (פוטר) water so is the beginning of strife”. The ת of תזכר expresses the feminine gender and refers to the animal in labour (i. e. the prefix is 3rd fem. sing., not 2nd masc. sing.: the subject to תזכר must be supplied “the mother animal”).