Whenever an atheist engages in any manner of discussion with Religionists regarding questions of Faith, the efficacy of prayer, the nature of God, the existence of God, the inerrancy of some sacred text, there are certain incredibly annoying arguments and 'points' that the Religionist will make over and over and over again. The vast majority of these points are logical fallacies. While Religionists employ nearly every logical fallacy known to humankind, here are a few that are used most frequently.
Bare Assertion Fallacy - The bare assertion fallacy is essentially a claim that X says A. X claims that X is true. Therefore A is true. This fallacy is used most commonly when Religionists seek to defend one sacred text or another. The Quran says A. The Quran says that the Quran is the Word of God and is never wrong. Therefore A is true. This is, of course, a complete and utter joke.
Argument from Ignorance - The Argument from Ignorance is a statement that because a specific proposition has not been proven false that it must be true. This fallacy is used most commonly when Religionists are discussing the existence of God. They blithely state that because atheists cannot prove that there is no God, that God must exist. This is very similar to another logical fallacy - Demanding Negative Proof.
Demanding Negative Proof - The burden of proof for any claim usually falls asymmetrically, that is, it falls more heavily on the party that is either making a positive assertion (X is True) or the party making a claim that deviates substantially from generally accepted understandings of reality (I Can Fly). The trick Religionists often play is that they either make a positive assertion that God Exists or an extraordinary claim that deviates substantially from generally accepted understandings of reality such as Jesus rose from the dead. They then demand that atheists DISPROVE their extraordinary claims and positive assertions. This is, of course, a logical fallacy. If I claim that I can fly, which deviates substantially from generally accepted understandings of reality, YOU do not bear the burden of proving that I cannot fly, I bear the burden of proving that I can.
Fallacy of a Single Cause and Causal Oversimplification - Causal Oversimplification is where a single and simple cause is posited for a solution or system which may be the result of numerous joint causes. This fallacy is used most commonly by Religionists when discussing Cosmology, Evolution, etc. The evolution of the Universe and the existence of life is an incredibly complicated and was caused by innumerable independent causes. Whenever confronted with cosmological evidence of the evolution of the Universe or biological evidence of the nature of evolution, Religionists engage in Causal Oversimplification. God is the first cause. God is the cause. God is the cause. No matter how complex the issue or how many joint causes might exist, God is ALWAYS the Cause. Religionists often accuse atheists of substituting The Big Bang instead of God and accuse atheists of making the same error. This is not actually the case. No atheist I have ever encountered has ever claimed that they knew what CAUSED the Big Bang. No Atheist claims that they know anything about what happened BEFORE the Big Bang.
Nirvana Fallacy - The Nirvana Fallacy is where one posits an idealized solution and then rejects a slightly imperfect solution because it fails to match the idealized solution. Religionists use this fallacy in conjunction with Demanding Negative Proof and Argument From Ignorance Fallacy whenever they discuss evolution or cosmology. They claim that because science cannot PERFECTLY explain all of creation, that because science cannot arrive at the Big Bang, it can only come with 0.000000000000000000000000000000000000000001 seconds, that represents an imperfect solution. Admittedly, Cosmology does not PERFECTLY describe the Universe. That doesn't mean that Cosmology is wrong. And it certainly doesn't imply that Cosmology should be rejected in favor of the utterly unproven assumption of an anthropomorphic God.
Moving the Goalpost - Moving the Goalpost is a tactic that Religionists employ with reckless abandon whenever they find themselves on the losing side of an argument. This tactic is a logical fallacy wherein the Religionist demands ever greater proof in response to any answer to a specific claim in order to nullify the effectiveness of a given answer. For example, the a Young Earth Creationist (YEC) posits that the Earth is 8,000 years old. The atheist produces evidence that carbon dating measured by the half life of carbon clearly indicates that the Earth is 4.2 Billion years old. The YEC responds that Carbon dating cannot be independently verified. The atheist produces evidence that in fact carbon dating correlates exactly with the fossil record in successive geological strata. The YEC then responds that God purposely created this confusion in order to test our Faith and demands proof that God DIDN'T do that. This is classic Moving the Goalposts.
No True Scotsman - This fallacy might as well be renamed the No True (Insert Favored Religion) Fallacy. This fallacy is trotted out whenever Religionists are called upon to explain the horrific things that have been done in the name of Religion, warfare, violence, tyranny, slavery, misogyny, etc.. The argument generally runs something like this. A Religionist says X is a religion of peace and our Holy Book calls upon us to be peaceful. Atheist recites passages from the Holy Book calling for violence and cites specific instances of Religionist violence. The Religionist then responds that No TRUE adherent of their Religion would do such a thing. This is essentially an ad hoc attempt to retain an unreasoned assertion. This also crops up with uncomfortable discussions regarding the Biblical Endorsement of Slavery. The Christian says that God abhorrs slavery. The atheist responds that throughout the book of Exodus, Judges, etc., the Bible provides very specific instructions for how to buy slaves, how to sell them, how to beat them, when to beat them, etc.. The Christian then responds that Christian would ever endorse slavery. The atheist then points out that Christians and Jews actively endorsed and participated in slavery for thousands of years. The Christian then responds by saying that that doesn't represent TRUE Christianity.
Argumentum Ad Populum - Argumentum ad populum is essentially the fallacy whereby one argues that because a position is popular, it must be true. This fallacy is used by Religionists in a wide variety of circumstances. Mostly it is used as a means of muting criticism by basically stating that atheism must be wrong because it has been rejected by billions of people. That because billions of people believe in the existence of God, God must exist. Obviously, this is an absurd proposition. Billions of people have believed innumerable false beliefs throughout human history. The fact that billions of people believe in God has absolutely no bearing whatsoever on Its actual existence.
Causal Misattribution - Causal misattribution is where one perceives an effect and incorrectly attributes that effect to a specific cause. This fallacy is most commonly utilized hen Religionists discuss the alleged power of Prayer. Religionists claim that God always answers prayers, but that God's answers to prayers are as follows: Yes, No, and Wait. As pointed out in this video the Yes, No and Wait responses to prayers are no different than those that would be offered by a jug of milk. Whatever the perceived effect of any prayer, Yes, No and Wait are ALWAYS correct, whether one is praying to God or praying to a jug of milk. Religionists perceive an occurrence and misattribute the cause of said occurrence to divine intervention. And due to the way in which they define how prayer works, their position cannot possibly be wrong, because the answer to ANY request will ALWAYS fall under either Yes, No or Wait. The fact that Religionists cannot properly provide evidence of their proposition regarding the efficacy of Prayer and move the goalposts whenever it is demonstrated that Prayer does nto actually work merely illustrates both the Demanding Negative Proof Fallacy and Moving the Goalposts.
Special Pleading - Special Pleading is the creation of an exception to a rule or exception to a general position based on an unjustified exemption. Religionists employ special pleading constantly. Religionists apply special pleading to God with reckless abandon. God cannot be tested because God says he doesn't like to be tested, therefore any tests to empirically determine God's existence, despite working on damn near everything else in the Universe, CANNOT be applied to God. The same goes for the efficacy of Prayer, the inerrancy of sacred texts, you name it. If you come up with na argument demonstrating factual or logical errors in a sacred text, the sacred text gets a pass because the normal rules of evidence and logic do not apply, or the verse does not mean what it says or some other specious exception. This fallacy is commonly used in conjunction with the Negative Proof Fallacy and Moving the Goalposts.
Together, these common fallacies, coupled with Faith that is by its nature is utterly impervious to evidence work to shield the Religionist from any critical examination of their belief system. So rather than wasting time attempting to refute these logical fallacies, simply point them out and move on to the next argument. And be assured there WILL be a next argument with a narrower set of goalposts. Because Faith is like a hydra, or a nest of cockroaches - obliterate one argument and the Religionist will simply make another specious one to take its place, stubbornly refusing to consider the proposition that perhaps, just maybe, the fact tha thtey have to work SO hard and employ SO many logical fallacies might just indicate that they might be wrong.