Leviticus 22:27

(to the effect that): What time thou callest to our mind the order of our oblations, as they shall be offered year by year, being our expiatory offering for our sins, when on account of our sins (such sacrifices are required), and we have none to bring from our flocks of sheep, then shall a bullock be chosen before him, in memorial of the righteousness of the elder who came from the cast, the sincere one who brought the calf, fat and tender, to Thy Name. A sheep is to be chosen, secondly, in memory of the righteousness of him who was bound as a lamb on the altar, and who stretched forth his neck for Thy Name's sake, while the heavens stooped down and condescended, and Izhak beheld their foundations, and his eyes were blinded by the high things; on which account he was reckoned to be worthy that a lamb should be provided for him as a burnt offering. A kid of the goats is to be chosen likewise, in memorial of the righteousness of that perfect one who made the savoury meat of the kid, and brought it to his father, and was made worthy to receive the order of the blessing: wherefore Mosheh the prophet explaineth, saying: Sons of Israel, my people, When a bullock, or a lamb, or a kid is brought forth according, to the manner of the world, it shall be seven days after its dam, that there may be evidence that it is not imperfect; and on the eighth day and thenceforth, it is acceptable to be offered an oblation to the Name of the Lord.

an ox, a sheep, or a goat either Scripture employs prolepsis, using the names they will have after they are grown. Compare “you strip the naked of their clothing” [Job 22:6], “the dead man will be put to death” [Deuteronomy 17:6], and “a falling person may fall” [Deuteronomy 22:8]. or these terms denote the entire species.

from the eighth day like a baby being circumcised, the animal must be at least one week old.

onwards i.e., after wards. This is borne out by the reappearance of the same word concerning Jonathan’s arrow [I Samuel 20:37].

שור או כשב, after the Torah had mentioned the various defective animals that are disqualified from being offered on the altar, it now mentions a number of situations in which even a perfectly healthy specimen of the ritually qualified animals may also not yet (or no longer) be fit as a sacrifice on the altar. Just as we learned that the monetary value of the animal is not the only criterion regarding its acceptability for the altar, so we shall hear now that there are still other considerations which can disqualify an animal frrom its being welcome to G’d as an offering.
If an animal has not yet reached the eighth day of its life, it cannot be used as a sacrifice. If the owner of said animal, or the priest offering it on his behalf, intends to consume it or part of it outside the holy precincts allocated for such eating by the Torah, or said owner plans to eat it past the deadline set by the Torah for consumption of such sacrificial meat, the sacrifice not only becomes disqualified but the penalty is extremely harsh. The technical terms for such disqualify cations are מחוסר זמן, too young, or אותו ואת בנו, if the mother animal had been sacrifice already on the same day, or פיגול, if the donor or priest had planned to deviate from the halachah governing where and for how many days such an animal could be eaten after it had been slaughtered. The intention known as חוץ לזמנו, eating part of it beyond the deadline set by the Torah even carries the karet penalty. The time limits are spelled out in our verses here.