1,165. Giving the Animal to a Kohein

177:2 If, while the owner is raising the animal, the kohein said, "Give it to me and I'll take care of it," the following rules apply. If the animal is unblemished, the owner is not permitted to give it to him because it will appear that the kohein is doing him a favor, in exchange for which the owner will give him the animal. This is prohibited because it's unfair competition (i.e., the owner might have given the animal to a different kohein had this one not relieved him of the burden of raising it). If, however, the animal developed a blemish during this time and the kohein said, "Give it to me so I can eat it," it is permitted because the kohein can slaughter it right away.

177:3 If the kohein doesn't want to accept the animal because it would too much trouble right now for him to raise the animal until it develops a blemish (at which point he would be permitted to eat it), he is not permitted to refuse. This is because it looks like he is disrespecting one of the Torah's priestly gifts. In any event, the owner is not allowed to give the animal to the kohein in order to annoy him or to have revenge on him (by burdening him with the trouble of raising it against his will). If the owner does this, the kohein does not have to accept it. Similarly if the owner sins - because he could have sold the animal to a non-Jew before it was born and didn't do so - the kohein does not have to accept it. Rather, the owner should raise the animal until it develops a blemish and then he should give it to the kohein.