[Xanga] Unanswerable questions

I think that at least the four following questions in Christian theology are, and will always be, unanswerable in human terms:

1) What is the nature and interrelationship of the Trinity?

2) How could Jesus possess a dual nature as fully God yet fully man?

3) How do the immaterial soul and physical body interact? (and, generally, mind-body problems. The causal closure of physics.)

4) What is the means by which determinism & predestination can be squared away with belief in free will and real consequences for immoral actions?

Anything else?