We know that the Big Bang occurred 13.8 billion years ago. Astronomers have even traced the approximate location where the universe emerged from a singularity. What matter (if any) that existed before that singularity exploded is unknowable.
To hypothesize that matter co-existed with God before the beginning of the universe is to claim that God is not truly God. That assertion insists instead there is something (unformed matter) which exists in its own right apart from God and which God depended upon and needed to create everything else. Essentially, such a claim asserts that Matter is greater than God.
