It is also clear from the foregoing that all creation is without succession.
 For succession is proper to movement: while creation is not a movement nor the term of a movement, as change is. Therefore there is no succession therein. See also argument 4 below.
Notes Creation, in other words, is the beginning of time. Or, put another way, time is defined as succession. This is why it is improper to speak of what happened “before” creation. There was no before.
 Again. In every successive movement there is some mean between its extremes: for a mean is that which a continuously moved thing reaches first before reaching the term. Now between being and non-being which are as the extremes of creation, no mean is possible. Therefore there is no succession therein.
Notes Shades of the fundamental theorem of calculus here? Let he who readeth understand.
 Further. Every making that proceeds by succession must needs take time: since before and after in movement are reckoned by time. Now time, movement, and the thing subject to movement are all simultaneously divided. This is evident in local movement: for that which is moved with regularity passes through half a magnitude in half the time.
Now the division in forms that corresponds to division of time is according to intensity and remissness: thus if a thing is heated to such a degree in so much time, it is heated to a less degree in less time. Accordingly succession in any movement or making is possible according as the thing in respect of which there is motion is divisible: either according to quantity, as in local movement and increase; or according to intensity and remission, as in alteration.
Now the latter occurs in two ways. First, because the form which is the term of movement is divisible in respect of intensity and remission, as when a thing is in motion towards whiteness: secondly, because such a division happens in dispositions to such a form; thus the becoming of fire is successive on account of the previous alteration as regards the dispositions to the form. But the substantial being itself of a creature is not divisible in this way, for substance cannot be more or less. Nor do any dispositions precede creation, since there is no pre-existing matter, for disposition is on the part of matter. It follows therefore that there cannot be succession in creation.
Notes Take “that which is moved with regularity passes through half a magnitude in half the time”, which is non-relativistically true. But it doesn’t matter if it’s relativistically false, because the main point is that the movement is reckoned by time. And did somebody say evolution? The intriguing point is substance cannot be divisible. Thomas is speaking of creation ex nihilo, of course, but it’s interesting to consider the definition of species (biological, not metaphysical) in this context. One species does not share the essence of another, even though they share material aspects. One to another there is a strict demarcation, a gap.
 Further. Succession in the making of things results from a defect of the matter, that is not suitably disposed from the beginning for the reception of the form: wherefore, when the matter is already perfectly disposed for the form, it receives it in an instant. For this reason, since a diaphanous body is always in the last disposition for light, it is actually illumined as soon as the luminous body is present: nor does any movement precede on the part of the illuminable body, but only local movement on the part of the illuminant, which becomes present.
But in creation nothing is required beforehand on the part of matter: nor does the agent lack anything for His action, that may afterwards accrue to Him through movement, since He is utterly immovable, as we have shown in the First Book of this Work. It follows therefore that creation is instantaneous. Hence in the same instant a thing is being created and is created, just as in the same instant a thing is being illumined and is illumined.
 Hence divine Scripture declares that the creation of things took place in an indivisible instant, when it says: In the beginning God created heaven and earth: which beginning Basil expounds as the beginning of time, and this must be indivisible as is proved in 6 Phys.
Notes Recall the “utterly immovable” meant unchangeable, metaphysically simple, constant. Creation is instantaneous! Ain’t you amazed, as Captain Aubrey would say? Everything there is—everything material+energy, that is—all at once. Meditate on this and try and imagine—for this is all you can do: try—what kind of power this requires. Yet another reason to fear God, where I use that word in its old sense.