
And the two simplest refutations are these:

(1)  What impact?  The only record of impact comes from the New Testament.
I have no guarantee that its books are in the least accurate, and that
the recorded "impact" actually happened.  I find it interesting that no other
contemporary source records an eclipse, an earthquake, a temple curtain
being torn, etc.  The earliest written claim we have of Jesus' resurrection
is from the Pauline epistles, none of which were written sooner than 20 years
after the supposed event.

(2)  It seems probable that no one displayed the body of Jesus because no
one knew where it was.  I personally believe that the most likely
explanation was that the body was stolen (by disciples, or by graverobbers).
Don't bother with the point about the guards ... it only appears in one
gospel, and seems like exactly the sort of thing early Christians might make
up in order to counter the grave-robbing charge.  The New Testament does
record that Jews believed the body had been stolen.  If there were really
guards, they could not have effectively made this claim, as they did.