ביצה ג׳:ד׳ - ג׳:ה׳

בכור שנפל לבור – a firstling with a blemish, which had not been shown to a Sage from the eve of the Festival day while it is still daylight to [potentially] permit it, and it fell into a pit on the Festival day, and he is afraid that it might die there.

ירד מומחה – who is a specialist to distinguish between a fixed blemish and a passing blemish.

ויראה – a blemish that it had [acquired] yesterday, if it is a fixed blemish.

יעלה וישחט – because there is no prohibition for use or handling [on Yom Tov] (or set aside in a shed for a sacrifice), and from yesterday, his mind was upon it.

ואם לאו לא ישחוט – this is how it should be understood, and if not, that this blemish that was upon it from the eve of the Festival was not a fixed [blemish] but rather on that day, it became a fixed blemish, even if it had passed and he brought it up, he should not slaughter it. And we don’t say that from yesterday, his mind was upon it and since it now has a fixed blemish, let’s slaughter it, for since yesterday’s blemish was not fixed, it is set aside in consequence of its being ritually forbidden.

אין זה מן המוכן – not because it was forbidden for use or handling did he prohibit it, for Rabbi Shimon does not have [the concept of] Muktzeh/something set aside, but because he permits its use on the Festival day, it is like he repairs it, and it appears that he made a legal decision that was decreed upon it because of it is forbidden by the Rabbis as being out of harmony with the celebration of the day. And this is how it should be state: His making it permissible is not a permit, and it is not prepared to be acceptable.

בהמה שמתה – we are speaking of the Holy Animals [for use in the Temple], as it is taught regarding it and on the Hallah that was defiled. For the Holy Animals that died it is forbidden to derive benefit from it and it requires burial, therefore, one should not move it from its place. But a secular/non-holy animal, we cut it up before the dogs. And these words [apply] when it was in danger from yesterday, when his mind was upon it, but if it was not endangered from yesterday, even a non-holy/secular animal, he should not move it from its place.

החלה שנטמאת – which is not appropriate for the Kohen on the Festival day, even to burn it or to give it to his dog, we don’t remove out of existence holy things form the world on Yom Tov, and even through animals eating it, as it is the decree of a Biblical verse that we do not remove ritually impure Holy Things from the world on Yom Tov.