One common criticism of divine simplicity is that it is an unscriptural dogma, and that in accepting it one subordinates Scripture to philosophical speculation. If simplicity is true and entails that talk of God is analogical then it would seem to imply that some passages require an interpretation different from their most immediate, literal one.
There are three points worth making. The first is that all biblical talk of God is going to require some philosophical interpretation. In fact, much of the Bible more generally will. Scripture is only made consistent under a certain interpretation. Are we to accept that Moses literally saw God’s back side? Clearly not, since God is immaterial and has no back, literally speaking. And what view of predestination and God’s providence are we to accept? This may largely depend on what view of free will you accept. Now, are we here “subordinating Scripture” to the idea that God is immaterial or that humans have libertarian free will? Maybe, but if we are then I don’t see anything wrong with this. There is nothing wrong with making Scripture consistent with one’s philosophical views so long as it does not radically distort what Scripture is saying (for instance, by saying that the Resurrection is just a metaphor).
Second, not all philosophical or theological doctrines need to be grounded immediately in Scripture. Maybe simplicity isn’t explicitly stated in scripture. In fact, this is obvious. But this is an unfair requirement to impose on defenders of simplicity. After all, neither is it stated explicitly in Scripture that God is three hypostases in one ousia.
You may reply that the idea is found implicitly there, but then I would say that so is simplicity. And this brings me to my third point, that by any reasonable criterion of something’s being scriptural, simplicity is scriptural. Simplicity is implicit in Scripture in that it follows from a strong doctrine of aseity and God’s providence, which is found stated in John 1:3 and Colossians 1:16. These passages say that all things were created by God. So it is true that whatever is non-identical to God is created by God. But if God had parts he would have to create his parts, and in so doing create himself, which can’t be true since God is uncreated and uncaused. Hence, God doesn’t have any parts and is simple.
One may reply that these passages should be taken loosely. But then I see no principled basis upon which to accuse defenders of simplicity of “subordinating scripture” while saying a “non-simple” view of God doesn’t. For now we are interpreting these passages in a less than strict sense in order to save the view that God is non-simple. And this seems to be precisely what simplicity was being accused of.