By a Sheva Brachos they had 2 cups to use for Bircas HaMazon and the Sheva Brachos. One was made of a silver and the other a simple glass cup. Is it preferable to use the silver one for Bircas HaMazon or for the Sheva Brachos? (or does it not matter which?)
Perhaps it would be better to use the silver one for birkas ha-mazon, which is a Torah mitzvah.
On the other hand, perhaps one can argue that the sheva berachos cup is passed round, and there is more of a kavod ha-tzibbur in using it for sheva berachos.
The first argument seems stronger, but I don’t see any obligation one way or the other.