What might it be that makes a building ‘come to life’? And what if it comes alive? Aristotle speculated on the apparent paradox that benefactors love their beneficiaries more than the beneficiaries love their benefactors. He says, ‘This is just what happens in the crafts too. Every craftsman loves the work of his own hands more than it would love him if it came to life. [. . .] Loving is a sort of acting’. 1 It is the same truth that humans are loved by their Maker more than they ever love him. Yet, the Introduction asserted, love moved minds to respond and to act upon things. In medieval theology and aetiology it entailed practical performance, which will be evidenced in our study. Furthermore, the architectural subjects seem to embody life infused by an effectual power such as is intrinsic in love—though it is difficult to see this from our vantage point. We will be in a better position if we start from the theology.