How Do I Know God Exists?

I wouldn't call it one of the most important questions I'd ever ask, but it is an interesting one.  Brought to you by Ray Comfort, the man renowned for his impassioned speech some time ago about the Atheist's Nightmare: the banana!  Now, that's not the entirety of his speech - and I say this because he got a bit riled up about people missing the first half - where he shows off a soda can and points out how it's got a tab for opening and the like, and how it's proof of a creator.  Well, that's fine and dandy, but if you watch the linked video with a horticulturist, they might have something to say -  that delicious yellow fruit we eat today was, in fact, selected and bred by man to make it more palatable - easier to grip, and the like.  The original banana was a rather distasteful looking thing.
So, what does this mastermind have for us now?  Well, we shall just see.

1. How Do I know God exists?
It’s amazing how many people think that God’s existence is a matter of "faith." They think that we choose to accept that an invisible God exists, without any real evidence for His existence. We just "believe."

How do you know?  Well, you don't, naturally.  You believe in it, and there isn't really any evidence.  There's a lot of stuff you could use to reinforce your belief, if you so choose, but you can't really know.  As Descartes once philosophized, the entire world and all you sense might be but an illusion, so you can hardly know anything.

Could you believe that a soldier’s barracks had no builder? Obviously someone put it together, because buildings don’t happen by themselves. The fact that the building exists is positive proof that there was a builder. Who could believe that a building—with its doors, windows, heating, air conditioning, carpet, electricity, etc., happened by accident, made from nothing?

Well, it could be one of those fancy inflatable ones that just sort of pop up when you throw down a little cube.  Or it could have been put together by a robot or a well trained ape, both of which, as we all know, have no souls.

Silliness aside, sure, yeah, I'm with you.  Can't have stuff made from processed and man made materials just sort of assemble into a building, I guess.  So?

Its design adds to evidence of a designer. For example, the door is made for a man to walk though. It has a handle and hinges. Windows are made for him to see through. The air conditioning keeps him cool in summer, and the heating keeps him warm in winter. The lighting helps him see when it’s dark, and the carpet is for his added comfort. The building was intended specifically for his use.

I suppose the design does add to the the evidence, not that it's really needed since I imagine militaries keep good track of which contractors built what and when.  But yeah, extra evidence, everything is working smoothly.  I don't know about carpet, though, soldiers aren't usually afforded that much comfort.

In the same way, creation is proof that there was a Creator.

Yeah?  Oh you mean the universe is proof of a creator.  Well, no.

Keep in mind that we can’t create anything from nothing. We don’t know how to begin. If you disagree, then make me a seed—-from nothing. Make it living, so that it grows into a plant that produces an edible fruit, and make it with the ability to create more seeds within the fruit, so that you can plant them and make more plants and more fruit. So if we can’t even make one seed, how intellectually deceitful is it for any rational human being to believe that nothing created everything?

Maybe you don't know how to begin, but we do know where to get something from nothing.  Not that it's relevant, since the idea that the universe was created in a 'big bang' from a singularity (which has plenty of evidence for it) necessarily includes the inability to know what conditions were like before the singularity.  Now, I'm not the most knowledgeable about these things, but what I've learned from Stephen Hawking is that a singularity is like a box of chocolates - you never know what happened before it, because it is by its very nature anathema to logic and understanding.  Which means that we have no idea what was before the singularity, and we can't - but we didn't start with nothing, we started with the singularity, because time did.

So I disagree, but I'm not going to make you a seed from nothing.  Not because I can't, but because I don't want to.  Anyway, if we're trying to copy evolution, it'd be more like 'make you a single celled organism from a rather complex mix of stuff', and then 'allow it several billions years to reproduce and be subject to natural selection until it had become a fruiting plant that, through concurrent evolution alongside animals, had evolved fruit edible by those animals'.  Or perhaps the animals evolved to eat previously inedible fruit, but you get the picture.
So, although we cannot even make one seed, we can comprehend quite a lot of what must have (did) occur to have 'nothing' create everything.

But there is more. The evidence shows that this earth upon which we live was intended for our use. We have lighting during the day so that we can see what we are doing. The sea breeze keeps the air fresh and cool, and the warmth of a massive ball of fire in the sky keeps us warm and dry. Cows give us succulent meat to eat and leather to wear. They chew grass and give us milk, and from the milk we get cream, cheese, butter, yoghurt, and ice cream. Sheep give us mouth-watering meat to eat, and wool from their back gives us warm sweaters, and supplies carpet for our comfort. Chickens lay eggs for us to scramble, and sacrificially provide finger-lickin’ meat on our plates.

Oh man, this is where the fun begins.  Yes, the evidence shows that light was created to occur during the day, because if it happened at night, it'd be useless.  And if we want to visit the sun, we just have to land at night time.  Or perhaps light occurs during the day because the earth rotates and thus the amount of light being cast upon any one part changes, and because we decided to name the parts when there's light 'day'?  The sea breeze keeps the air fresh, which is why everyone living inland has died of suffocation in the stale air.  It keeps us cool too, which is a good counterbalance to that big-ass ball of fire heating everything up.  We have to live with that damn warm thing though, since if it wasn't there we'd get all wet all the time, because all the water would continue to evaporate in the extreme cold, and the vapour wouldn't just freeze out of the sky without any input of heat.  We'd still have light, though, because that comes from somewhere else, apparently.

Cows were engineered by some unknown Creator to give us meat to eat and leather to wear, which is good because otherwise BDSM play would be a lot less exciting.  Same for two other specific animals, although only chickens give up their meat sacrificially so I guess Ray doesn't eat lamb or beef from dead cows, he gets it sliced off the live animal for him.
This was all designed by God, by the way.  Which is why chicken eggs come helpfully pre-salted and peppered, and sheep wool is only allergenic to some people (sinners).  Cow milk was made for humans, which is why people become lactose intolerant unless they consume it regularly after infancy.

We have oceans that are rich with tasty fish for our dinner; the soil yields juicy fruits for the table and a huge variety of vegetables to keep us healthy. Trees breathe out oxygen for us to breathe in, and we breathe out carbon dioxide for them to breathe in.

Fish all look the same because God willed it so, not because they share a common ancestor.  Whales and dolphins are mammals and possess vestigial hind limbs and a very long fossil record of their re-entry to the water (warning: video does not contain entire evolutionary tree of whales or even all of the fossil examples because it is short) because God thought it would be funny, not because they were mammals that re-entered the water.  Fruits grow in the soil!  Fruits and vegetables were designed to be edible, which is why almond shells, apple seeds, cherry seeds, apricot pits and others contain cyanide, many berries are poisonous and potatoes contain solanine (like nightshade).  We breathe out carbon dioxide for plants, which is good because nothing else does, and they create oxygen for us, which is good, because nothing else does (except photosynthetic bacteria in the oceans which do most of the oxygen production worldwide).

We have eyes to enjoy the beauty of this amazing creation, ears to listen to melodious music, as well as hear the song of a myriad of beautiful birds that usher in the morning light. We have a mass of taste buds to relish mashed potatoes and gravy.

Eyes are for seeing beauty, not evolved (and there are a number of good evolutionary trees to describe this evolution) to find light for photosynthesis or to detect predators, and ears are for listening to birds, which are for singing.  Taste buds are for tasting potatoes(?).

Add to this the wonder of man being made for woman and woman for man, and the fact that dogs give man enjoyment and keep him company. He has brilliant white snow upon which to ski, massive waves upon which to surf, the joys of blue skies, green grass, and white beaches with amazing and crystal-clear water.

Wait, I thought you believed that woman was made for man and man was made as an ego trip by god?  Also, not sure why you included dogs in your sentence about the wonder of compatible sexual organs.

Not much else to say, except that apparently snow was always intended for skiing and waves for surfing.  God's great plan, I suppose.

On top of all this, gravity keeps his feet firmly grounded so that he doesn’t spin off into space, as this massive ball of dirt upon which he lives spins around at the breath-taking speed.

Wow, all that and gravity?  It all sounded pretty simple up till you mentioned gravity.  Good thing we have it, because the breath-taking speed is pretty fast.  Although, you're kind of simplifying it by calling it 'dirt'.  It's really more 'water and lava and a mostly iron core, and also a bit of dirt on top with the water'.

Anyway, gravity isn't something to require a creator - if it didn't exist, the universe wouldn't be like it is and we wouldn't be here to witness it.  Anthropic principle and all, you know?  Speaking of...

The amazing design all around us screams of the unspeakable genius of an incredible
designer.

No wonder the Bible calls the professing atheist a "fool."

So there is no question as to whether or not God exists; which brings us to the second question.

The amazing coincidence all around us screams of 'if it wasn't like this, we wouldn't be alive'.  As in, no gravity means no formation of planets means no life means no humans to know about no gravity.  If the universe hadn't worked out like it was, we wouldn't be alive to say it was all done by a god.  So it is amazing, but it's also to be expected.

Not to mention all the things that make no sense for an omnipotent and presumably omniscient being to have created, but make perfect sense to have evolved - see vestigial traits, sharing an eating hole with a breathing hole, and other poor 'design' choices in general.
No wonder I'm calling Ray Comfort an 'intellectually disabled man who confuses necessary conditions and completely sensible evolutionary concepts with elements of design'.
Yes, if you're talking about the God as depicted in the Bible, there is absolutely no doubt that he doesn't exist.  It's really quite impossible for something so completely contradictory, retarded, and obviously wrong to be inspired by an omnipotent being, or for an omnipotent and all-loving being to be so hateful and incompetent and just plain wrong.
We may just look at that second question in the near future, Ray.  Be prepared!