q and a on abc, page-57

I doubt if he is making those emails up. It is very common for people like him to receive them.
Atheist Sam Harris, author of "Letter to a Christian Nation", has received death threats from people quoting their favourite book as justification.
So has Christopher Hitchens. And Salman Rushdie. And that Danish cartoonist.
It is not very common for religious believers to receive such threats from atheists in the name of their beliefs