Did Kepler (or if it was Newton) think God's thoughts after him?

In a sense, yes. For one thing, God beforehand knew, and in that sense "thought" every error that would ever be believed by fallible creatures, even errors that have only been believed by mere novel figures, like Eustace Clarence Scrubb thinking he could find a British Consul in Narrowhaven, because he was at sea and had not grasped it was in another world, or Gandalf, Aragorn and a few more believing that Sauron's men, orcs and ringwraiths held Frodo captive, because of that depersonalised, but very astute and cruel, wreck of a human person showing them the mantle and mailcoat of Frodo. God even knows all possible errors that are not even realised in novels.

And so, of course, God knew the errors of Kepler and Newton too - or at any rate of Newtonianism (it is a bit dubious if Newton shared the errors of most Physicians attached to Newtonian physics).

God did neither predetermine who should believe what error, nor ignore who actually does so. God watches every move, of every angel, man, beast, plant, mineral or even atom, but does not take away free will, except on limited occasions, rather arranging the other circumstances (animals, plants, minerals, water, atom, aether, time, timing and other circumstances of any coincidence) so as to make the will of each man yet capable of reaching salvation as free as possible.

But God, though not predetermining what we actually choose, did predetermine what was possible to choose, and so He did predetermine and formulate in advance what moves would be possible, either naturally, or by miracle, or by diabolical deceptions.

If a chessboard has eight by eight squares, no willing on part of any player will let him move ten squares in a single direction, even diagonally the limit is eight, without getting outside the board, nor straddling squares.

God made the chessboard of our free thought and our free will, but that fact does not predetermine the moves of the players - our selves, our guardian angels, our tempters like Devil, World or Flesh, or those of God Himself, though He made the chessboards with a view on what moves He was going to make.

Nor are the moves predetermined because God watches the moves we make now and will make tomorrow since eternity past. And because he sees - and in the better case arranges - what side will win, the white or the black, the "chessgame" about each act or the "chessgame" about our eternity.

So, in a sense every one who is in error - including Kepler and Newton - every and all are thinking God's thoughts after Him. But God thought these errors as errors, so the one who sees them as errors rather than believing them is even better thinking God's thoughts after Him.

In another sense also they were thinking God's thoughts after Him : namely insofar as they are partially true.

If Copernicus was partially right about Venus and Mars orbitting Sun, Tycho Brahe was more true in adding this was not so about Earth, but rather Earth was the centre that the Sun orbitted.

If Kepler and Titus and Bodes were partially right about Venus and Mars orbitting Sun so that they form elliptic orbits with Sun in one of the two foci, Riccioli was more right in stating that with Sun and Earth it was the inverse, Earth was (and remains) in one focus of the annual orbit of the Sun.

If Titus and Bodes were partially right about Venus and Mars forming a series of distances to the Sun of the orbits, a Geocentric accepting that would be even more right in saying but in the case of Sun and Earth it is the opposite relation of centre and orbit, of "circled" and "circling" body (or would you say "of ellipted and ellipting body", as per Kepler?), and of course Mercury is off either way, as Einstein ventured to explain with relativity, though I forgot the details.

And supposing Newton was partially right about Mass of Sun attracting, while previous movement was tangentially projecting Venus and Mars, which I am less sure about, Sungenis would in such a case be more right to say that Sun in its turn was attracted to the centre of Mass of the whole Universe, which providentially was the place where God placed Earth.

God does not need a discursion through simple steps to a more complex conclusion, but if he had needed that, Kepler, Titus and Bodes, and possibly also Newton would have been taking for the "final outcome" what was rather "next to final sketch", with an inversion to Geocentricity added. This inversion being of course conducive to very decorative patterns in the planetary orbits, if these are taken with Earth as a reference frame, which they should. You see, since God is a Catholic and not a Calvinist, He set the place in which the angels worship him more on decoration than on simplicity. Exactly as the Catholic Church (excluding Vatican II errors) is wont to do with places where we worship. Along with angels.

Two little additions, so as not to get confused about cosmology or metaphysics. One is, the movements here described or briefly alluded to are only abstracts, ignoring the daily movement of the Universe. The concrete movement of any celestial body any day is very close to a perfect circle - since the varying (and concretely as said florid) distances from Earth are those of orbits taking a longer time by far than a mere day. The other is this - whatever the nature of "gravitation" as it is called (no one doubts apples fall to the ground) the celestial bodies have have gravitational reasons to get where they are getting, but these would probably not be sufficient to get them there unless they were directed by angelic beings, in fact by good and unfallen angels (Satan being the "fallen morning star" was probably ex-conductor of either Venus or Mercury - and has been replaced as such, being himself now bound in Hell). In the case of a bicycle, its surface of contact, its speed, its weight, all contribute to getting it forwards, but without a driver, it would very soon have the steering wheel start wobbling and thus fall to the ground. Whether or not this is the reason, I think angels are in fact conducting the heavenly bodies, since this is how the Bible in three places (or only one of them if you rely on a Protestant Bible) describes them. But I think the consideration of why the orbits stay as they are would be enough to prove there are angels too.

Hans Georg Lundahl
Bpi, Georges Pompidou
Vigil of St James and
St Christina, Virgin and Martyr
24-VII-2014

Who of them said it? According to this site it was Kepler:

An "unorthodox" Lutheran, Kepler had a deep love for Christ and the inspiration and authority of Scripture. He is frequently quoted as saying, "O God, I am thinking Thy thoughts after Thee."

Man of Science, Man of God: Johann Kepler
by Christine Dao
[Citing recommendation: Dao, C. 2008. Man of Science, Man of God: Johann Kepler. Acts & Facts. 37 (3): 8.]
http://www.icr.org/article/science-man-god-johann-kepler/