cellio | daf bit: Kiddushin 52

The mishna is still discussing the objects with which a man may or may not betroth a woman. (Betrothal calls for a gift of a certain, small, monetary value.) Today we learn: if a kohein (priest) betroths a woman with his portion of the offerings (the part designated for the priests), she is not betrothed. This is true whether it is of the higher degree of sanctity (the sin-offering, eaten only by priests) or of the lower (peace-offering, eaten by priests and the person who brought it). This is, it will be explained later, because these offerings belong to God; the priests may eat them, but they do not belong to the priests, and a man must own the object he uses to betroth a woman. The mishna then makes a similar statement about the second tithe, which also goes to the priests -- no betrothing with them, either. This is the view of R' Meir. R' Yehudah says: if he did it unwittingly she is not betrothed but if he did it deliberately, she is. (52b)

(Today's daf is 55, and part of a long discussion arising from this mishna.)