This man is only as "credible " as you choose to make him.When I sat down and really READ the bible, not skipping over or making excuses for the hard verses that teach election I realized that God is indeed sovereign.
This mans work is less credible that the works of Spurgeon , Edwards, Bottner, Piper,Sproul etc.
His is not a scholarly book , but a book with an agenda . He mis reads some scripture to make his point...some thing that someone that only has a Sunday interest in the Bible will surely miss
One more thing Mack, Far fewer Calvinists move to Arminianism than Arminians move to Calvinism. That is because serious study (not cutting and pasting work that agrees with you ) will bring one to see the truth.
Do more "more-or-less" orthodox Christians become Mormons or Jehovah's Witnesses or do more Mormons and Jehovah's Witnesses become "more-or-less" orthodox Christians? But that's not a valid argument is it?