I picked up a new book recently from my local used book store, by Alister McGrath and I came across this [1] startling passage:
McGrath wrote:The atheist believes that there is no God, but his position is a matter of faith rather than fact. He cannot prove beyond all reasonable doubt that God does not exist, just as the Christian cannot prove with total conviction that God does exist: Both are positions of faith.
I hate comments like this, I really do, and it pains me even more when a person with McGrath’s education makes it. This is not something a theologian should ever put into print.
I call this line of observation the “Faith of the Gaps” and it usually crops up when someone reflects on the disputations that go on between Atheists and Christians, and it usually comes from the Christian camp. I think it is a terrible mistake, it seems like Christians like McGrath are trying to level the playing field by attributing faith to the Atheist like faith is something to be ashamed of, or like faith some kind of concession of defeat for the Atheist. ...
If they can cast atheism as a religion then they can cast doubt on it in their own minds, and among their fellow believers, merely by asserting their own, contradictory religion.
Most Mormons don't know that much about the vast majority of non-Mormon religions in the world, but they all feel pretty confident that these other religions aren't true, because they have a testimony that Mormonism is true. And knowing this, most don't feel compelled in the least actually to engage the arguments. If they can cast science, atheism, and so forth in these same religious terms, voila! They get their refutations for free.
Mormonism ceased being a compelling topic for me when I finally came to terms with its transformation from a personality cult into a combination of a real estate company, a SuperPac, and Westboro Baptist Church. - Kishkumen
I haven't read the book, so I'm speaking from pure ignorance here as to what McGrath was trying to say. I do think that statements like this have more of a polemical, rather than epistemological flavor to them. That is, the statement is trying to level a playing field and establish connections.
What I mean by that is this. You correctly observe that faith is a fundamental virtue of Christianity, and a mode of "knowing" something. I put scare quotes there because I really don't want to get into a debate about the nature of knowledge. The problem for a Christian, at least in debating the average atheist, is that the atheist will neither concede that faith is a virtue, nor that it is a valid mode of knowing something. There is a gap in discourse because the average atheist really can't see any connection between what they think of as virtue and knowledge and what the theist does. At its worst it gets downright condescending and offensive at times, witness the multitude of idiotic statements by the village atheists that populate MD.
So, to establish a connection, the theist will reach for some common ground. Most atheists (excepting of course the complete idiots), will concede that knowledge, at least scientific knowledge, is one of probabilities. The theist then tries to draw a connection between faith and probabilistic reasoning because neither can claim an absolute knowledge. The polemical point is to show some commonality and create an area for discourse. As you point out, comparing faith and probabilistic reasoning may not be the best connection to try and make.
The real problem as I see it, is that the average atheist and theist are so far apart in worldviews, usually both through ignorance, that there really isn't a way to bridge the gap. What's sad is that this doesn't need to be this way. Take for instance John Locke, the first philosopher as far as I can tell to introduce probabilistic reasoning as part of epistemology. Of course Locke was also an apologist for the Christian faith. However, I'm not so sure he would consider them to be the same thing. Probabilistic reasoning would give evidence for the Christian faith, but I'm not sure Locke would say that the evidence and the means of obtaining it are the same thing as faith itself.
By the way, I think there's plenty of blame to go around on both sides, both sides have widened the gap for their own reasons.