Loftus feels like Christian morality has a flaw in that "a Christian...always has an excuse for doing...wrong...he'll [God] forgive me". (p. 43)
Apparently, Loftus hasn’t read the book of Romans. Any reading of that book should be sufficient to show that the Christian ethic does not work on that basis. Again, there certainly are people who are guilty of the kind of thinking Loftus cites but, it is contrary to the outworking of Christian thinking.