It has become ever clearer to me that one of the convictions that underlies my metaphysical assumptions is that Man's creative ability is real; yet mainstream, classical, 'traditional' Christian theology has no place for Men to be able genuinely to create: that is, for a Man to be able to to add something new to to God's existing creation.
This exclusion of the possibility of creation is a consequence of the mainstream Christian's understanding of the nature and attributes of God.
God is assumed to have created everything from nothing (creation ex nihilo), and to live outside of time (such that God knows everything that including all possible futures), and to be omnipotent and omniscient.
Putting all of these together - for the mainstream-classical theology divine creation has-been done wholly by God, has already-happened; and is complete and unchangeable (since it is beyond time).
From this perspective; there are two basic ways we can know - which CS Lewis terms contemplation and enjoyment (and which are described and explained in this essay, but without using the contemplation-enjoyment nomenclature - which distinction is explained in his autobiography Surprised by Joy, and elsewhere).
For a classical, mainstream Christian theologian like Lewis, contemplation and enjoyment are the only possible ways of conscious 'knowing' - with enjoyment a higher form of knowing.
(There will also be ways of 'unconscious' knowing - in the sense of animals, or plants, that implicitly 'know' many things, because they behave adaptively; but without possessing what most people would recognize as explicit, conscious awareness of their knowing. However, I believe they do, because everything does, possess some consciousness, of some type)
Contemplation is when we retain the stance of a separate observer - it is, in effect, knowing-about something.
For a Christian, a Man might contemplate God, or the works of God - and this means knowing-about such things; by paying attention, having experiences, studying, learning.
A higher form of knowing God would be enjoyment, or 'communion'.
This would be when someone (perhaps a Saint, or a resurrected Man in Heaven) inhabited the divine mind, able to perceive and know God by means of a direct connection; becoming joined-with God's creative will - but retaining one's own identity as a distinct creature (created individual).
Man in full communion with the divine remains conscious of himself; but knows God's work from the inside, and knows his own part in it.
(It is this retaining of personal identity that differentiates the Christian understanding of divine communion, from the 'Eastern' (Hindu, Buddhist etc.) idea of Nirvana - in which the individual Man loses his distinction, his 'self'; and becomes dissolved-back-into the divine-whole, from which he originated.)
But communion is not creative; since creation is done.
What seems like creation to mortal Men is - by this analysis - a result of our limited perspective - and is actually just a selection and arrangement of already-created material.
For the mainstream-classical Christian, Men cannot truly create, in a primary sense; because Men are creatures/ created-Beings; and only God is capable of true creation.
But for me, as for CS Lewis's best friend Owen Barfield, there is a higher state than enjoyment - which is creation - or what Barfield terms Final Participation.
This includes communion, but also involves knowing oneself to be adding-to and enhancing already-existing divine creation: that is, becoming a co-creator of God's creation.
Therefore, Man can (potentially) become a creator with God, creating in harmony with what already exists.
It can be seen that for co-creation to be true, several of the classical-mainstream assumptions about God must be discarded. Because it can be added-to; creation is no longer regarded as existing outside time, nor as being complete and finished.
Man is no longer understood as wholly a 'creature' - but as an 'embryonic god': capable of developing to participate in primary creation of that which is new and unforeseen.
Thus, a recognition of Man as potential creator goes-with a rejection of the assumptions that God is omnipotent and omniscient, that God created everything from nothing, and that creation is complete and beyond time.
Instead; creation is recognized as ongoing - within time - incomplete and capable of expansion.
In other words; creation is God's original project; and a project in which Men may develop to participate.
To summarize; if we are to regard Man as capable of real creation; we must reject the classical, mainstream, tradition Christian theology; and adopt different metaphysical assumptions concerning God, creation and time.
Conversely, if we choose instead to adhere to the classical, mainstream, tradition Christian theology; we must reject the possibility of Man being a true creator; and assume instead that the highest form of being that Man can aspire to is an ultimately passive state of 'enjoyment' in communion with God.
How to decide between these incompatible metaphysical explanations of Christianity - apart from intuition?
The Bible as a whole is apparently ambivalent and self-contradicting on this topic; but the Fourth Gospel (of "John" - especially Chapters 13-17 inclusive) strongly suggests that Men (in the new dispensation of Christ) can and should aspire to become co-creators: that is loving 'friends' of Jesus Christ and God, rather than (as in the previous era, before Christ) merely obedient servants of God.