Board Thread:General Discussion/@comment-3250527-20140916050148/@comment-1173941-20141022135642

Yeah, who knows? I mean, according to the 2005 Q&A, Holy Sword's lowest level ability was creating a bright flash of light. It's very likely Holy Sword offered weapon enhancement for ones Sword, and the fact that his shield also counted as his sword's sheath, the enhancements extended to that.

But Kawahara never fully explains what it does, does he?