Yes Chris, that's what I meant. If the bullet had been deflected, passed through other material(s), or was near the end of its effective 'energy range', then the leaves of the book, end on, would have some effect in slowing the bullet further. This is due to the effect of the preceding shock wave, and the bullet itself, causing the individual leaves to attempt to fan out, increasing the overall area, albeit minutely, and absorbing both shock and impact. Hitting the face of the book, under the same conditions, the bullet would probably pass straight through, as the shock wave would 'bend' and deform the once flat and compact impact area, offering less resistance.
Of course, within the bounds of effective energy/velocity, the bullet would pass through at whichever angle, or part, the book was penetrated. But, some weird things can happen in ballistics. I've seen 7.62mm rounds penetrate engine blocks, whilst the same type of bullets, under similar conditions, have been deflected off car bodywork.
You have to wonder though - maybe the Bible did stop,the bullet - after it had passed through the body of the man who's haversack it was in!!!