Spencer, Duane Edward. 1979 (2000 reprinting). Tulip: The Five Points of Calvinism in the Light of Scripture.
I don't know if Tulip is the best best book for those curious about Calvinism, but it is one of the most user-friendly guides on the subject. In just under eighty pages, Spencer uses Scripture to clearly and concisely prove the validity, the reliability, the rightness of this often misunderstood doctrine. (I honestly don't know if doctrine is the right word. But subject didn't sound right in that sentence. And theological system sounded too wordy. Topic might have worked instead. The point is with the mention of the mere words "predestination" or "Calvinism" tempers begin to flare and minds are already intensely made up.)
I find this book refreshing for several reasons. One is that Spencer came from the Methodist tradition. He started out (like many Calvinists do) in the Arminian camp. He knows the other side because he's lived it. Yet in his Bible studies, he was convicted of the rightness of "Calvinism." He could not, would not remain as pastor in the Methodist church knowing that his new beliefs so radically differed from those taught and upheld by Methodists. Two is that Spencer is not afraid to tell it like it is. He sees that mainstream Christianity has through the course of several centuries fallen away from the truth--in this regard, in this matter--and has begun upholding, supporting a doctrine that was time and time and time again refuted as heresy. Perhaps heresy may seem a bit harsh. And Spencer certainly isn't advocating the position that mainstream Christians aren't really and truly Christians. But what I'm saying is that he is pointing out that what a good majority of modern Christians hold to be true, take for granted to be true, would have at one time--at many times in fact--been ruled unbiblical, unsound, untrue.
At the time I first read this it was a shocking concept. But one that I've come to see as true as sad as that might be.
It's logically organized and clearly written. It makes for a great thought-provoking read as well as for a handy reference guide. But more importantly, it is solidly based on the Bible. Using verse after verse after verse after verse, Spencer argues for a biblical understanding and urges Christians to actually consider what the Bible actually says while forgetting their own preconceptions about what the Bible says. The Bible is the only "proof" anyone will ever need when it comes to the rightness of the doctrine of election. And Spencer uses it well.
However, I will say this. I found one spelling mistake and two other tiny errors. I wish--I really wish--they weren't there. One is that there is a reference to 1 Timothy 1:9 that should read 2 Timothy 1:9. And the second is similar. A II Thessalonians 5:23-24 that should read 1 Thessalonians 5:23-24. Perhaps these mistakes don't appear in other editions.