And the 123rd prohibition is that we are forbidden from taking out any meat of the Pesach offering from the place that we have gathered to eat it.1

The source of this commandment is G‑d's statement2 (exalted be He), "Do not bring any of its meat outside."

In the words of the Mechilta,3 "The expression, 'outside,' means outside the place where it is eaten."

One is prohibited to eat whatever is brought outside, and it is considered like treifah.4

Our Sages said in tractate Pesachim,5 "One who takes out meat of the Pesach offering from one group to another, even though he transgresses a prohibition, it is still pure." One who eats it [also] transgresses a prohibition."6

There7 it says, "One who takes out meat of the Pesach offering from one group to another is not punished unless he places it down. This is because the expression, 'to take out' [hotza'a] is used, just as regarding Shabbos.8 If he does place it down, he is punished by lashes.

The details of this mitzvah too are explained in the seventh chapter of Pesachim.