Exodus 13:12

12 you are to give over to the LORD the first offspring of every womb. All the firstborn males of your livestock belong to the LORD.

Read Exodus 13:12 Using Other Translations

That thou shalt set apart unto the LORD all that openeth the matrix, and every firstling that cometh of a beast which thou hast; the males shall be the LORD'S.
you shall set apart to the LORD all that first opens the womb. All the firstborn of your animals that are males shall be the LORD's.
you must present all firstborn sons and firstborn male animals to the LORD, for they belong to him.

What does Exodus 13:12 mean?

John Gill's Exposition of the Bible
Exodus 13:12

That thou shalt set apart unto the Lord all that openeth the
matrix
Or "the womb", as in ( Exodus 13:2 ) , and this phrase, "set apart", explains the word "sanctify" there, and shows that it signifies the separating of such to the use and service of God, causing it to "pass", as the word F4 here used signifies, from a man's own power and use, to be the Lord's only: and every firstling that cometh from a beast which thou hast;
or "even every firstling" F5, explaining what is meant by what opens the matrix or womb, even every firstborn of a beast; though Jarchi interprets it of an abortion, what comes before its time, that this also should be set apart to the Lord; this must be understood of the firstlings of clean creatures, fit for food and sacrifice, such as the firstlings of cows, sheep, and goats, ( Numbers 18:17 ) as distinguished from unclean ones in the following verse: the males [shall be] the Lord's;
which explains what sort of firstborn of man and beast were to be set apart for his use, not females, though the first that opened the womb; but males.


FOOTNOTES:

F4 (trbehw) "et transire facies", Pagninus, Montanus, Fagius, Vatablus, Drusius, Cartwright; so Ainsworth.
F5 (rjp lkw) "etiam quicunque vel quicquid aperuerit", Junius & Tremellius, Piscator, Ainsworth.
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