Existence is a relatively simple concept -- it is defined as that which consists of either matter or energy. Therefore if a god exists, it must be composed of either matter or energy.
The opposite must also be true. If a god is not composed of matter or energy, then that god, by definition, does not exist. Thus to argue that a god exist, despite a total absence of matter or energy, is to argue, existence equals non-existence, which is a complete contradiction.
If a god exists, then physical evidence is really the only methodology by which we can ascertain that a god exists. Of course, this does not require direct physical evidence -- we cannot perceive black holes directly, but we know that they exist due to the effects of their gravity wells on surrounding matter, as well as the flashes of energy that are released as captured matter crosses the event horizon. But since "existence" is defined as that which is composed of matter or energy, the proof of existence must be some evidence of that matter or energy.
Evidence is defined as that which impacts our physical senses in some manner, either directly, or through some translating device such as a spectrograph or an oscilloscope. Since our sensory organs are designed to perceive the effects of matter and energy, it is through the evidence of the senses that we can determine the existence or nonexistence of things.
If I argue that something exists, but then claim there is no way to detect it, my argument contradicts itself. Let's say I tell a deaf man that I hear a deep, loud sound coming from a speaker. If he lays his hand on it and feels no vibrations, he has every right to be skeptical. If I say that this loud sound does not have vibrations, he may then pull out his trusty microphone or other sound wave detector. If this instrument detects no sound in the vicinity, can I still tell him that this loud sound is occurring? At some point, if my definition of "loud sound" basically boils down to "that which is the opposite of any evidence that a loud sound is occurring," then clearly my approach to truth needs a little work.
This approach helps clarify the truth value of the proposition that a god does not exist. If a god exists, then sensual evidence of some sort is required to determine the existence of that god. If a god is not made up of matter or energy, then that god does not exist, since that which is not composed of matter or energy -- does not exist. If a god is made up of matter and energy, then it is subject to physical laws. Since it is bound by physical laws, miracles are impossible, because miracles are, by definition, violations of physical laws. Likewise, a god cannot be all knowing and all-powerful, since both attributes would violate the basic tenets of physical laws. All knowing would require instantaneous knowledge of all matter, past, present and future, which is clearly impossible, while all powerful would require the ability to break the bounds of physical laws, which brings us back to the realm of nonexistence.
If a god is subject to physical laws, then praying to a god makes about as much sense as worshiping a black hole, begging the Sun to grant you favors, or circumcising your son to appease the moon. If a god is not subject to physical laws, then the concept of a god is synonymous with the concept of non-existence.
Why is there such resistance to the fact that a god does not exist? Many people redefine "God" within their own minds as "a potential form of matter or energy that has not been discovered yet," or "that which could exist in an alternate universe," or something to that effect.
However, either a criterion for determining truth exists, or it does not. If such a criterion exists, then it must be objective, and based on the evidence of the senses and reason, which precludes the existence of any deities. If no such criterion exists, then both everything and nothing is true, and agnosticism, atheism, superstition, religion and the belief of the flying spaghetti monster are all equally valid.
If an objective criterion for truth exists, then it cannot logically be applied according to whim, or only in situations that feel emotionally comfortable. Through this logical method we can determine no god exists.
1. God drowns the whole earth: In Genesis 7:21-23, God drowns the entire population of the earth: men, women, children, fetuses, and perhaps unicorns. Only a single family survives. In Matthew 24:37-42, gentle Jesus approves of this genocide and plans to repeat it when he returns.
2. God kills half a million people: In 2 Chronicles 13:15-18, God helps the men of Judah kill 500,000 of their fellow Israelites.
3. God slaughters all Egyptian firstborn: In Exodus 12:29, God the baby-killer slaughters all Egyptian firstborn children and cattle because their king was stubborn.
4. God kills 14,000 people for complaining that God keeps killing them: In Numbers 16:41-49, the Israelites complain that God is killing too many of them. So, God sends a plague that kills 14,000 more of them.
5. Genocide after genocide after genocide: In Joshua 6:20-21, God helps the Israelites destroy Jericho, killing men and women, young and old, cattle, sheep and donkeys. In Deuteronomy 2:32-35, God has the Israelites kill everyone in Heshbon, including children. In Deuteronomy 3:3-7, God has the Israelites do the same to the people of Bashan. In Numbers 31:7-18, the Israelites kill all the Midianites except for the virgins, whom they take as spoils of war. In 1 Samuel 15:1-9, God tells the Israelites to kill all the Amalekites men, women, children, infants, and their cattle for something the Amalekites ancestors had done 400 years earlier.
6. God kills 50,000 people for curiosity: In 1 Samuel 6:19, God kills 50,000 men for peeking into the ark of the covenant. (Newer cosmetic translations count only 70 deaths, but their text notes admit that the best and earliest manuscripts put the number at 50,070.)
7. 3,000 Israelites killed for inventing a god: In Exodus 32, Moses has climbed Mount Sinai to get the Ten Commandments. The Israelites are bored, so they invent a golden calf god. Moses comes back and God commands him: Each man strap a sword to his side. Go back and forth through the camp from one end to the other, each killing his brother and friend and neighbor. About 3,000 people died.
8. The Amorites destroyed by sword and by Gods rocks: In Joshua 10:10-11, God helps the Israelites slaughter the Amorites by sword, then finishes them off with rocks from the sky.
9. God burns two cities to death: In Genesis 19:24, God kills everyone in Sodom and Gomorrah with fire from the sky. Then God kills Lots wife for looking back at her burning home.
10. God has 42 children mauled by bears: In 2 Kings 2:23-24, some kids tease the prophet Elisha, and God sends bears to dismember them. (Newer cosmetic translations say the bears maul the children, but the original Hebrew, baqa, means to tear apart.)
Taking it's title and cue from GII Videos amazingly successful "10 questions every Intelligent Christian must answer", this video explores a different angle.
Instead of delving into Biblical Incoherence, it looks at, and asks questions related to the God Concepts' incoherence, especially the commonly defined Judeo-Christian God.
"When I became convinced that the universe is natural, that all the ghosts and gods are myths, there entered into my brain, into my soul, into every drop of my blood the sense, the feeling, the joy of freedom. The walls of my prison crumbled and fell. The dungeon was flooded with light and all the bolts and bars and manacles became dust. I was no longer a servant, a serf, or a slave. There was for me no master in all the wide world, not even in infinite space. I was free--free to think, to express my thoughts--free to live my own ideal, free to live for myself and those I loved, free to use all my faculties, all my senses, free to spread imagination's wings, free to investigate, to guess and dream and hope, free to judge and determine for myself . . . I was free! I stood erect and fearlessly, joyously faced all worlds."