Matter and form; two separate words; however, in this world, the world we dwell in, matter never comes without form; and form never comes without matter... (Aristotle calls this hylomorphism 'from, hule - wood, timber; morphe, shape and form').
So, the world is there in its sturdiness, in its shapeliness...both at the same time - inseparable.
But when we refer to them by signs, that is words, we can separate them; this in Aristotles Categories, is called separation by definition; that is by defining or signifying them by words, signs or pictures, we can tease apart the signification in a way we can't with the thing signified.
And we can do this because the sign and the signified are always separated; and it's also separate from signification or signifying.
In Plato, the Good, is the highest good - the most perfect; we can say in Western monotheism it is not separable from our notion of what God is: where God is found, there goodness is found; where goodness is found - there is God.
Can God not be God ... is a sentence we can write, like other sentences ... like: can God not be Good; but this is to take one of the attributes of God and separate it from him, when the attribute is intrinsic or essential to him.
Our notion of the Good is only a shadow of real Good; like our notion of what God is only a shadow of the real God.
A stone is something you can pick up and hold in your hand; what then is a stone that cannot be held? The word 'stone' is not a stone, but merely sign of one, and by being a sign separable into its parts; you cannot take apart an actually existing stone in this way: a stone in virtue of its stoniness is something that can be picked up and held; how then, to separate a stone from its stoniness and to deny altogether the possibility of holding it?
Take a photo of a stone, or draw or paint one; and then erase it, leaving only the bare outline of one; the mere hint of a stone.
And then look at the really existing stone and do the same ... one could take a hammer to it; hammer it down to dust; so the question turns, revolves and turns away from this to another; which is merely the same under another guise - can you take away the dustiness from dust? Etc, etc, etc till:
So you can: in the imagination - the imagination being the theatre of the possible and impossible; for the world is, and what is cannot be otherwise in its thisness (haeiccity).
We can place God on a page and put him under erasure; likewise we can place the World on a page and place it too under erasure; but look up - away from what was erased: the world is still there - it shines forth - there it is, standing in its sway - the act of erasure was only to erase a word that you yourself wrote; the word is not the world but merely refers to it; it's not the first word, but merely your word; likewise with God, and the signs (ayat) of God and the signs of the signs of God - ie the letters, words, sentences, pictures ...
It's worth noting that all this is in line with the third option outlined in @Tobolski's answer - the essentialist reading.