Paul Williams recently posted an entry on his blog, titled Further thoughts on Christianity versus the Jewish Bible, in which he invokes a passage he has been hitting people with for years: Deuteronomy 30:11. His essential argument is a simple one: this or that English translation of Deuteronomy 30:11 gives the impression that the Mosaic Law is not difficult to keep, therefore any Christian (or even New Testament author) who says otherwise is contradicting Deuteronomy.
Readers can visit the relevant blog entry, and see, for example, Sam Shamoun, offering a detailed response to Mr. Williams' argument (assuming the censorship-prone Williams has not deleted said comment(s) by the time one reads this). I would like to make one small contribution to the discussion by noting what Rashi had to say on this issue. Here's a portion of Rashi's commentary on the relevant verse, as it appears in my copy of Miqra'ot Gedolot:
In the underlined portion, Rashi argues that the text is stating the commandment is not covered (or concealed, or hidden, which interestingly lines up with the KJV). Rashi goes on to support his stance by providing other examples of where the relevant verb means to cover or hide.
This, then, raises a question: being that even eminent Jewish authorities (who cannot be accused of some sort of Christian bias) understood the text as stating that the command is not hidden or covered, we need not consider it as necessarily being a comment on how difficult the Law is. For an analogy, I can put a quantum physics text book right in front of you (thus it will not be hidden, you will not have to go looking for it), but that in itself does not mean making it accessible to you is the same as it not being difficult for you to follow.