Gregory of Nyssa: "[...][the activity] is separated from the first by the fact of not being a nature, but a movement of nature (φύσεως κινησις)[...]"

"We say that one works metal or wood, or carries out another of such activities (ἐνεργεῖν). Therefore, language presents at once both the art and he who exercises the art, so that if one separates one thing, the other cannot subsist. If then, the two realities are thought one together with the other, that is activity itself and he who acts through it, how is it that in this case one says that on the first substance (τῃ οὐσίᾳ τῃ πρωτῃ) follows activity that produces the second substance, as if mediating in itself between the one and the other, without being confused with the first according to nature, nor being tied to the second? For [the activity] is separated from the first by the fact of not being a nature, but a movement of nature (φύσεως κινησις), and is not united to that which results because it does not have as proper result a simple activity, but an active substance." (CE I, GNO I, 88, 4-17, tr. Maspero 2007, p. 40)