Having taken Eric Metaxas' writing style to task, I'm going to perhaps make up for it a little by pointing out some terrific things I've learned from Amazing Grace about William Wilberforce's career as an antislavery crusader.
Here's Wilberforce's reaction to the umpteenth bump in the road -- Britain's failure to demand an immediate end to the French slave trade when Napoleon had abdicated the first time in 1814:
My spirits are quite lowered by it, yet let us do what we can and trust to God's blessing on our labours.
There it is, nice and simple and short: the same reaction that we always should have when Right suffers a setback.
I should add that he then mounted a wildly successful petition campaign, presented a million signatures to Parliament, played a very smart political game and got his measure to amend the peace treaty with France passed by large margins in both Houses, and won the day. That's a good example to follow, too.