פירוש על עבודה זרה 63:3

The Jew does not want to use the earthenware for the wine that is in it. He wants to use the shard only to even out the legs of the bed. In an abstract formulation, this is called “one who wants the object (the shard) to exist for some reason other than the prohibited substance (the wine). Two amoraim argue over whether such a usage transgresses the prohibition of using Hadrianic earthenware.