We must understand, therefore, that as the Son, who alone knows the Father, reveals Him to whom He will, so the Holy Spirit, who alone searches the deep things of God, reveals God to whom He will: For the Spirit blows where He lists. We are not, however, to suppose that the Spirit derives His knowledge through revelation from the Son. For if the Holy Spirit knows the Father through the Son's revelation, He passes from a state of ignorance into one of knowledge; but it is alike impious and foolish to confess the Holy Spirit, and yet to ascribe to Him ignorance. For even although something else existed before the Holy Spirit, it was not by progressive advancement that He came to be the Holy Spirit; as if any one should venture to say, that at the time when He was not yet the Holy Spirit He was ignorant of the Father, but that after He had received knowledge He was made the Holy Spirit. For if this were the case, the Holy Spirit would never be reckoned in the Unity of the Trinity, i.e., along with the unchangeable Father and His Son, unless He had always been the Holy Spirit. When we use, indeed, such terms as always or was, or any other designation of time, they are not to be taken absolutely, but with due allowance; for while the significations of these words relate to time, and those subjects of which we speak are spoken of by a stretch of language as existing in time, they nevertheless surpass in their real nature all conception of the finite understanding. (Book I, Chapter 3, Part 4)

Origen anticipates our potential misunderstanding and attempts to correct it. There are still, it seems to me, some complicated mutual dependencies in his schema.

Must God be changeless? Does being perfect require eternal continuity? Must God be perfect?

To use any of these words - changeless, perfect, or eternal - requires a great leap of imagination.

As creatures of time and space we are intimate with change, error, and endings. How do we presume to know their opposites?

I perceive in the gospels a Jesus who changed, who was evidently on the edge of error, and who came to an end before transcending that end.

Might this insight also be a purpose of the incarnation?

The image is the Deposition of Christ by Rubens.