Quotation for Eruvin 34:23

And [it] is practiced in every place and at all times by males and females. And one who transgresses and goes even one more ell than three parsa [outside of the city] is lashed. And so [too], if he goes even one more ell outside of the two thousand ells adjacent to the city, he is struck with rabbinic lashes for rebellion. And Ramban, may his memory be blessed, wrote (on Sefer HaMitzvot LaRambam, Mitzvot Lo Taase 321) that that which Rambam, may his memory be blessed, said in his Book of the Commandments (Sefer HaMitzvot) that the prohibition of boundaries is forbidden from the Torah past two thousand ells [from the city] - and so [too], what he said in his great composition (Mishneh Torah, Laws of Sabbath 27:1) that he recanted from this and wrote that the measurement of the Torah is three parsa - is all a mistake, since we do not have a prohibition of boundaries from the Torah at all. And so is it elucidated from many places in our Gemara, which is the Babylonian [Talmud] that we rely upon in all of our words. And the teacher (Ramban) gave numerous proofs for this on Commandment 313 (it should read, 321) of the negative commandments. And he understands, "let no one leave (yetseh)," to be like "let no one carry out (yotsee)" - [just] like there is an opinion in Tractate Eruvin 17b that understands it this way.