Leviticus 22:26-33 - Arthur Peake's Commentary on the Bible

Concluding Rules for Sacrifice, not specially directed to Aaron, as they concern all persons intending to sacrifice. A calf or lamb or kid offered (as firstborn) is to be kept till the eighth day (cf. the rule of circumcision, Leviticus 22:12). The law is an ancient one; cf. Exodus 22:29 f. (Book of the Covenant), where it is joined with the law of the offering of the first-born which underlies the practice of circumcision. For the prohibition of the sacrifice of cow and calf on the same day, cf. Exodus 23:19; perhaps in certain forbidden rites the calf was treated as the kid evidently was. Or the motive may have been similar to that of Deuteronomy 22:6. Thank offerings, like peace offerings, are to be offered with a view to acceptance, i.e. with the observance of all the rules. Nothing must be left over to the next day; cf. Leviticus 7:15, and, for the Passover, Exodus 12:10; contrast Leviticus 7:16; Leviticus 19:6; also (a more general rule) Exodus 23:18, The final exhortation to this section is brief, but it lays its emphasis, now familiar, on the holiness of the whole people, and its connexion with that of Yahweh.