Perhaps you have your own theology or religion. But there is not a difference between your A-space and your B-space. They are coextensive in Catholic theology. There is no “existence” that is not either God or God’s creation.
I’m presenting this as a premise. I’m saying
what if there is existence beyond what God is and what God created. You have to at least put your toe in the water and ponder the premise before dismissing it out of hand, otherwise why bother even doing any philisophical exercise?
So let’s ask what are the usual arguments that God is omniscient, omnipresent, and omnipotent.
1) The Bible says so
Let’s assume that the Bible is accurate when God states that he is the alpha and omega, the beginning and the end. Let’s also assume that my theory of A-space and B-space is accurate. What are the ways that both premises can be accurate?
1a) God is only aware of B-space
God is truthful in stating his power and accomplishments because that is all he knows. He is the beginning, the end, and all things in-between for as much as he can comprehend.
1b) God is aware of A-space, yet describes his power to humans in a way that we can understand.
Often times when asked about passages in the Bible where the plain meaning of words might not jive with other passages or with what we know of the world today, apologists (including budding ones on CAF) will explain that God and the Bible will use words that convey meaning to a people that may be limited in their capability of understanding. If my two premises above are true, perhaps God is aware of something beyond him; and when God talks about his infinite wisdom and power and presence he understands that it’s within the realm of B-space yet doesn’t see the need to sully his message to a people who could never really comprehend it.
2) It is argued that the Creator MUST be omniscient, omnipresent, and omnipotent.
Numerous theologians and apologists have argued the the being who created the universe must possess those three qualities. So we take a leap and assume this crazy idea of A-space and B-space is true, that God created all that is B-space and controls all within it. It could be argued that is not
necessary that God knows all of, has power over all of, and is present within all of A-space. It is only
necessary that he knows all of, has power over all of, and is present within all of B-space.
Remember those three terms are not in the Bible, but are used in arguments by people who assume that there is nothing beyond God and his creation. Since you’re getting hung up on the notion of relative omniscience, let’s define new terms to describe God’s power, presence, and knowledge within the universe he created. I could have accurately used the suffix “homo” but decided to go with “mono”.
God is “mononipotent”. He is all power within the universe as he and we know it.
God is “monoscient”. He has all knowledge within the universe as he and we know it.
God is “monopresent”. He is everywhere within the universe as he and we know it.
So to sum up and get back to the question the OP posed, I argue that it is possible that God may not be truly all-knowing.