Um, okay, whatever.
The actual text from the PHB has "shield" italicized, which by precedent and standard procedure of the rules, indicates that the sentence refers to the spell name, not to the shield as an object. The same is true of Luminous Armor.
So, as I said, any more than just circumstantial evidence? The argument in favor thus far holds very little water. The Magic Vestment spell clearly calls for "armor or shield touched." Nowhere in the spell descriptions are Shield, Mage Armor, and Luminous Armor referred to as a suit of armor or a shield in the context of them being an object, they are always referred to in the context of the spell name through italicization.
And yeah, maybe this is slightly more of an argument now, because I'm becoming more convinced that you can't actually do this.