Spinoza's Ethics: I.P35: God's Control

Of particular interest to me here is the Latin word used for power - potestas. As discussed earlier, there are two words used by Spinoza for power: potentia and potestas. Potestas carries the sense of organized and controlling power as opposed to unfolding and expressive power. In some sense, it is analogous to a snapshot of reality as opposed to a video. Spinoza is using the static form here because it is being conceived as in the power of God or as the expressed as opposed to from the power of God or as the expressive form of power. As such, it is necessary and not optional. It can be no different than as it exists. This forms a fundamental component of Spinoza's system: "it is as it has to be."

Quicquid concipimus in Dei potestate esse, id necessario est. 

Whatever we conceive that is in the power of God, it is necessary.

Demonstratio: Quicquid enim in Dei potestate est, id (per propositionem præcedentem) in ejus essentia ita debet comprehendi ut ex ea necessario sequatur adeoque necessario est. Q.E.D. 

For whatever is in the power of God, it (by P34) must be comprehended in [God's] essence in such a way that from [the essence's necessity] it follows that it is necessary.