'Neck' in the Bible

Every firstborn of a donkey you shall redeem by [substituting] a lamb [as a sacrifice for it], but if you do not [wish to] redeem it, then you shall break its neck; and every firstborn among your sons you shall redeem [that is, “buy back” from God with a suitable sacrifice].

You shall redeem the firstborn of a donkey with a lamb; but if you do not redeem it, then you shall break its neck. You shall redeem all the firstborn of your sons. None of you are to appear before Me empty-handed.