A question asking about the mind of the flesh and the mind of the Spirit (Romans 8:6) is not the same because I am not asking about the mind of the Spirit, i.e. the Holy Spirit, plus my two verses in question are in Ephesians, not Romans. Of course, the Holy Spirit may be directly connected to being "renewed in the spirit of your mind" in Ephesians 4:23 - one of the verses I ask about - but I want to know more about the spirit of the mind. What is it? How does it work, and how could it be 'renewed'?
The second, related verse I ask about seems to indicate an entirely different spirit force that "works in the children of disobedience" as in Ephesians 2:2. The verse seems to indicate it is not connected to the Holy Spirit, but to some princely "power of the air". What is this spirit of the air which works in disobedient ones? Does it work in their minds?
So, to put the verses in order and to quote them fully (K.J.V.):
"Wherein in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience" (Eph. 2:2)
"And be renewed in the spirit of your mind." (Eph. 4:23)
I understand the first verse to speak of a person prior to becoming renewed in the spirit of their mind (because the latter verse speaks of Christians.) This is why it seems to me that those two 'spirits' seem to stand in opposition - there are two opposing spirits here.
If the answer is based on the whole message of the Ephesians letter, that would save jumping about all over the New Testament, though I appreciate that it may be necessary to include other parts when concluding the answer. And I specifically ask those who believe in spiritual, invisible powers that can control one's mind to answer.
Please note: I have deliberately NOT used the tag 'Holy Spirit' because my question is about the spirit of the mind, and that of a spiritual power of the air, and it is that which I seek enlightenment about.