What do you believe about reading books on Christian topics by authors that have a Calvinistic background? What does the Bible say? Can we take their word for their particular subjects that they discuss? For example, Josh McDowell has a book on Christian apologetics, yet he works with Campus Crusade for Christ and I assume is a Calvinist. Since someone such as Josh may be a Calvinist, how do we take their word for it, when it comes to interpreting the Bible on certain matters, especially if they have and may put Calvinistic interpretations?
Also, how do we make sense of Calvinist people such as Josh McDowell who contribute a great deal to Christian apologetics? They seem to lead a good life, providing solid evidence for Christianity, yet follow certain practices of the Bible with the wrong interpretations. What I'm trying to get at is that I don't understand why and how it works when some people that have strayed from the Bible's teachings, contribute good things to Christianity.
What makes something right or wrong is whether it matches what God has said. "Sanctify them by Your truth. Your word is truth" (John 17:17). A particular individual or a person of a particular religious background doesn't imply that we can accept what he states on a subject without checking it against the standard for truth. "Beloved, do not believe every spirit, but test the spirits, whether they are of God; because many false prophets have gone out into the world" (I John 4:1). Even the apostle Paul was checked by the Bereans when he taught them, and for that, the Bereans were praised (Acts 17:10-11).
I read books by people from a variety of religious backgrounds. I realize that different people have insight into things I may not have thought of before. Many times those ideas are worth investigating. For example, I have a wonderful little book on child-rearing in my library. The author has a great way of putting things and has insightfully applied a number of passages that have gotten me to see some deeper meaning. However, this same book has a chapter dealing with original sin and blames a child's mischievousness on its "sin nature." I know this is contradictory to what the Bible teaches. I can clearly see how the author misapplied the Scriptures and skipped several very significant passages. So while most of the book is useful, I am careful to warn people about the bad parts if they want to borrow the book.
Most of the modern denominational writers are not very good. Oh, they turn out some good prose, but they don't back up their statements with Scriptures. The majority of their books make you feel good, but they have no meat. I might read through some for ideas, but until I can find that it matches what is taught in the Bible, I don't use them.
Still, you can also get interesting information for dealing with people of certain religious beliefs when you read their writings. It helps you see how they came to their conclusions, whether they are right or wrong. It is especially useful to find a person who is of a particular belief, but who sees some of the flaws in his own denomination. For example, one of the best definitions of faith in miracles that I have is written by a charismatic who was trying to find true evidence of modern-day miracles. After ten years of searching, he had not found it, but I suspect that this is because he was using an accurate statement of what constituted a miracle and a belief in a miracle. Sadly he kept looking instead of realizing that the Bible states miraculous gifts no longer are given. But his insight is all the more telling because he is certain that it should exist -- he just had not found it yet.
So long as you don't think that something is right just because so-and-so said it, you can use the writings of others to broaden your knowledge.
Well in response to your answer, I am curious about why certain people of Calvinist (or other religious) background still provide solid proof that we can use to prove that Jesus existed and resurrected, among other evidence topics, even though they themselves adhere to various beliefs that aren't biblical. Do you think God both uses and allows people such as these who have unbiblical backgrounds to provide some expertise on matters that are biblically right?
The assumption you are making is that because a person holds an incorrect belief in one area of knowledge, it must follow that he is wrong in all areas of knowledge. I hope you can see that this cannot be true. For instance, A. T. Robertson is well known for his expertise in the Greek language. He wrote a classic work called Word Pictures in the New Testament. I use it frequently, but I'm careful of his discussions concerning the necessity of baptism, such as in Acts 2:38, because I know his personal bias makes him an unreliable source in this matter.
Since a Calvinistic belief system does not impact a person's objectivity in regards to the factual nature of Jesus' existence or his resurrection, I'm not surprised to find good source material on this topic among those who follow the belief system of John Calvin.
Still, remember that what makes a particular line of argument good is because it matches the truth taught in the Scriptures -- not because of who made the argument or what the religious belief of a particular individual.