Reference for Bava Metzia 12:6
ואי ס"ד תקפו כהן אין מוציאין אותו מידו אמאי נכנסין לדיר נמצא זה פוטר ממונו בממונו של כהן
But Rabbah answered him: You speak of the sanctity of a firstling — [this proves nothing]. I could well maintain that even if the priest has seized it we take it away from him, and still it would be forbidden to shear or to work [this animal], because the sanctity that comes of itself is different.<span class="x" onmousemove="('comment',' The sanctity of the firstling is independent of any action on the part of the priest, as it is sacred from birth, in accordance with the Biblical Law. It cannot therefore be compared with the sanctity of an object that has been consecrated by a human being. ');"><sup>11</sup></span> R. Hananiah said to Rabbah: There is [a Baraitha]<span class="x" onmousemove="('comment',' The principal place where this law is taught is a Mishnah, Bek. 9a; cf. also ibid. 11a. ');"><sup>12</sup></span>