Just another thought... Whenever anyone other than the cleric in question holds the sword, they find themselves unable to raise the blade up into a striking position. If they try to, it's as though some invisible hand was pushing down on the end of the blade.
I really liked your idea as well Hero, but from the looks of it they probably won't be going on any church related missions in the foreseeable future. Who knows though, depending on how it plays out I may still use the idea
Once again, I truly appreciate all of the help and great ideas!
I had a lot of fun with a sort of similar scenario with a 9th level paladin once.
The high priest of his church asked him to give up a +2 longsword he found, as "it was needed for a great warrior of the church". He did it, and couple months later, the high priest sent a messenger saying he needed his help again. When he showed up, the high priest gave him his old sword back -- having converted it into a +5 holy avenger. For, of course, the paladin, having achieved traditional "name level" of old school D&D (though we were playing 3e at the time), was the great warrior who needed the weapon.