Witnesses and explanation are two different things. And what about Jonah? Got any witnesses there too besides the fish? How does one live in a stomach full of digestive juices without being crushed by smooth muscles into a pulp and deprived of oxygen for three days and live, scoff-free?
How does a dead body come back to life? Please show me a "logical" sequence of this phenomenon. Petrification (decomposition) begins minutes after the breathing stops. The brain dies for all practical purposes four minutes after being deprived of oxygen. How does a dead Lazarus (dead for four days!) come back to life? Miracles, right?
Well if you are going to believe miracles why is painless birth an obstacle. The Church seems to have always believed Mary remained a virgin after the birth. We can only believe that if Christ was born supernaturally the way he appeared to the apostles through the closed door...
petrification=putrification (spellchecker...)