Cardinal Newman, the leader of the Oxford Movement in the Church of England who converted to that of Rome in 1847 wrote a book entitled An Essay in the Development of Christian Doctrine.
He describes the problem in Chapter 8, Section 2, Paragraph 12.
That great portion of what is generally received as Christian Truth is in its rudiments, or separate parts, to be found in heathen philosophies and religions.
He lists amongst these a doctrine of the Trinity, the ceremony of washing, the rite of Sacrifice, the Divine Word, the doctrine of the Incarnation, angels and demons, a sacerdotal order and a new birth.
He says that Mr (Henry) Milman argues from this that
These thing are in heathenism, therefore they are not Christian
but that we (Cardinal N and the RCC) prefer to say
These things are in Christianity, therefore they are not heathen.
He explains
From the beginning the Moral Governor of the World has scattered the seed of truth far and wide over its extent, that they have variously taken root and grown as in the wilderness, wild plants but living; and hence that as the inferior animals have an immaterial principle in them, yet have not souls, so the philosophies and religions of men have their life in certain true ideas they are not directly divine.
A little later he says one way Providence has imparted divine knowledge to (the Church) is by allowing her to draw and collect it together out of the world and so to suck the milk of the Gentiles.
In so far as this question is a resource request, Cardinal Newman is someone who addressed this issue.
