I like this dork a lot in Legacy. In that format, 4 toughness potentially ties up the ground pretty well against decks like Merfolk, Thresh, or Goblins, while also slowing down their deployment (unless they have vial).
In Vintage...? I kind of like my dorks to be overwhelmingly powerful, cost 2 or less, or at least trade favorably with Shops creatures. This spirit utterly fails that test. It can't block or kill Lodestone. Can't even stop a flipped Delver or a Goyf after turn 2.
I'm glad this card exists, but I can't see why I'd run this over Rule of Law if I wanted the Enchantment type, or Canonist if I wanted anti-storm tech.
I think this guy opens deck creation room. 8 white Rule of Law in a UW deck with counters, factories, Spirit of Labs, Erayos (with heavy turn 1 mana accel) 4 rules that can attack or be walls vs early critters...it's not bad at all. Add in 4 of the better true believer and you're in business.