1. The concept that the bible is the inerrant word of God
There are countless contradictions in the bible that are obvious (and many more that are not as evident). One just has to read the bible (not even study it in detail) to find these. I recall a pastor tell me that if the bible is not inerrant then we might as well just throw the whole thing out. The bible is an important book like others books. And inspired by God is a much more accurate manner to describe the bible. However it is far from inerrant.
While there are many discrepancies in the bible, here are just a few examples of some; let's start with Genesis chapters 6-9 about Noah and the flood, there are two stories combined. One account has two, a pair of every kind of animal. Another account says seven pairs of the clean animals and only two of the unclean animals. Another one from the Old Testament is Psalm 145:9 and Jeremiah 13:14 where in the prior God is good and merciful to all and in the latter God will destroy all that worship a different deity.
In the New Testament, Matthew 10:34-36 describes Jesus telling the disciples that He came not to bring peace to the world, but a sword. However, in Matthew 5:43-48 Jesus says to love your enemy. Paul of Tarsus in Galatians 3:28 wrote: "There is neither Jew nor Greek, slave nor free, male nor female, for you are all one in Christ Jesus." However 1st Timothy 2:11-15: says "A woman should learn in quietness and full submission. I do not permit a woman to teach or to have authority over a man; she must be silent...". Religious scholars unequivocally agree that Paul wrote Galatians but did not write 1st or 2nd Timothy. The historical Paul of Tarsus was well known for supporting women's equal rights.
2. Warped theology by Christian exclusivists which includes ignoring the human rights violations in the Middle East
A friend of mine, a professor of theology recalled a disturbing event while on his trip to the Middle East in the 1980s; a Christian fundamentalist attempt to bomb the Dome of the rock to somehow start the events for the second coming of Jesus. This action was endorsed by American Christian fundamentalists. Christian Zionists or dispensationalists believe Jews should control the Middle East to set the stage for the second coming of Jesus. Yet Christian Zionists do not endorse Judaism.
Jerry Farwell believed that a Jew would be the Anti-Christ. Of course if he had really studied his theology he would understand that Roman ruler Nero during the time of antiquity was considered by the early church to be the anti-Christ. Nero was persecuting early Christians. "666" was a code used by John of Patmos to disguise his criticism of the Emperor Nero---the Greek alphabet assigns a numerical value for each letter, and Nero Caesars full name adds up to either 666 or 661, depending on how you translate the name.
To understand the biblical gospels academically, the second coming of Jesus and the end of the world were thought to have been within or shortly after his lifetime. As one example, Jesus is quoted as saying in Luke 9:27 "But I tell you truly, there are some standing here who will not taste death before they see the kingdom of God." So for Christian Zionists or dispensationalists to act in this manner (ignoring the atrocities) is not only unethical but also prophetically erroneous. The conflict in the Middle East involves a denial of the right to vote, segregation, violence and the death of innocent civilians, and many are children. This type of warped theology is demeaning true Christianity which include, first and foremost the care of innocent women and children.
3. Refusal to get acquainted with people of other religions
Exclusive Christians have generally no interest in learning another religion. I spoke to a local pastor suggesting I give a short lecture on Islam. He replied that this would be polarizing to Christians. This pastor wasn't really criticizing Islam with this statement but instead was acknowledging that many Christians know almost nothing more than the propaganda by certain media outlets that Islam is equated with terrorism. On the contrary, two of the 'Five Pillars' of Islam include the concern and charity for the needy and the other is fasting to remember those, especially children that don't have enough (or anything) to eat.
According to Buddhist scholar Edward Conze, Buddhist missionaries had been proselytizing for centuries (before and after the time of Jesus) around Alexandria, Egypt. To say Buddhism influenced early Christianity is not by any means unprecedented. Yet exclusive Christians have little or no knowledge of Buddhism and for the few that do, to say to them that Buddhism likely influenced Christianity would result in a staunch rebuttal.
4. More concerned with legalism than humanism
Some Christians are overly concerned with legalism (rules) and forgetting all together the concern and well-being of one's neighbor (humanism). Which should include all neighbors of all faiths. The legalistic perspective has sin being perceived as disobedience to God and/or offending God and the humanistic one describes sin as what degrades or harms the person. But in reality, there is really no difference; disobedience to God is like disobeying a father or mother with the child doing something to harm themselves or others. A father or mother is seldom stunned with being offended directly. As an example, it is commonplace for a child to occasionally say they hate us (as parents).
Parents typically want the child to learn to adapt within society and respect all persons. If parents tolerate misbehavior, then the child will believe it to be acceptable in society. Since humanity was made in the image of God, then it would be logical to assume we would mimic His actions as parents. Sin is about what harms ourselves and subsequently others, not so much about offending God. God is concerned about the well-being of all of his children.
5. Thoughts, quotes, philosophies, and music from other religions have no merit
In the social media, and news, one will rarely (if ever) see an exclusive Christian quote someone like Rumi, the Dalai Lama or Gandhi. Why is this? Is it really because they are considered to have no merit by these people? Additionally, if a famous Christian musician becomes ill or dies, the exclusive Christian will ask for prayers yet if a Hindu or Muslim with similar fame faces a tragedy, seldom will there be the same request for prayers.
6. Overly concerned with homosexuality as being a serious and grave sin
Seldom do we hear in the conservative Christian media strong condemnations of frivolous sexual activities. Society has a tendency to elevate in status the irresponsible sexual undertakings of the young male, despite it being highly discouraged in the bible. This is not at all the case of homosexual activities. The bible clearly discourages irresponsible sexual activities but this is not exclusive to just homosexuals.
The responsible homosexual couple is much more likely to adopt orphans than the heterosexual couple simply because they cannot conceive. All of the synoptic Gospels quote Jesus saying "whoever may cause to stumble one of the little ones, better is it for him if a millstone is hanged about his neck, and he had been cast into the sea." The proper nurture and care of children is central in Christianity. Jesus certainly didn't say cast into the sea the homosexual as a consequence for their sins. As a matter of fact, Jesus never even once mentioned homosexuality in the gospel accounts of his life.
7. Belief that religious/theological academia is somehow falsehood, destructive and/or distorted
An article in the Christian post from John Piper where he reveals "Why PhDs in Theology Commit Adultery; Says They Cheat 'Probably More' Than 'Less-Educated People'" is just complete nonsense. According to the Associated Press Journal of Marital and Family Therapy, 54-57% of spouses commit adultery and the large majority of these people do not have Phds in theology.
It is a belief by many exclusive Christians that biblical scholars like Dr. Bart Ehrman or Dr. Michael Coogan agenda is to attack Christianity. Instead of understanding their results are from dedicated and countless hours of honest research and academia. Both are top scholars in their field of study. What exactly might either of these scholars or others like them gain by trying to undermine Christianity or another religion? I mean really? Bart Ehrman reads Hebrew and Greek and Michael Coogan reads Hebrew, Greek and Aramaic. I doubt most of their critics have even the smallest grasp of these ancient languages.
8. Their concept of being "saved"
Countless times over the years, I've been approached by evangelical Christians in their effort to 'save' me as if I just fell off the boat. "I was raised Roman Catholic" I say; yet they still ask me if I'm saved, and I often respond with "saved from what"? Then when they get to know me and that I am a scholar of religion, it stifles them. One has to wonder if some of these people are too consumed with the being saved concept forgetting the importance of love your neighbor and enemy. If every Christian in the world including those overly concerned with personal 'sin' and being 'saved' would adopt (or foster) just one orphan, there would be no orphans and a lot less hungry children.