There's something we can test: Show us something we understand about how life came to be.
As other people have pointed out, this is god-of-the-gaps theology. It is bad religion and theology. In brief, God must never be inserted between regularly occurring members of the universe. This makes God a part of the universe and Christian doctrine is very plain that God is NOT part of the universe. If you want to read more about this, I suggest the book Christian Belief in a Postmodern World by Diogenes Allen. In fact, science got the idea of no gaps from Christianity.
There is a lot that we understand how life can arise from non-life. You asked for "one thing". I'm going to give you several. You can see some summaries here:
http://www.hhmi.org/research/investigators/szostak.html
http://homepages.ihug.com.au/~panopus/abiotic.htm
We know the organic compounds that make up the basic building blocks of life -- amino acids, sugars, nucleotides, etc. -- can come to be by very common chemical processes:
1. RF Service, A biomolecule building block from vents. Science 281: 1936-1937, Sept. 25, 1998. Synthesis of ammonia at underwater volcanic vents. Ammonia is a necessary building block for amino acids.
2. MP Bernstein, SA Sandford, LF Allamandola, Life's far-flung raw materials. Scientific American 281: 42-49, July 1999. Astrochemists show that complex carbon compound, including amino acids, are present in interstellar clouds.
3. J. P. Amend, E. L. Shock , Energetics of Amino Acid Synthesis in Hydrothermal Ecosystems, Science 281: 1659 - 1662 ,11 Sep 1998.
4. Marshall, W. H. 1994. Hydrothermal synthesis of amino acids. Geochimica et Cosmochimica Acta 58: 2099-2106.
1. Kawamoto K, Akaboshi H. Study on the chemical evolution of low molecular weight compounds in a highly oxidized atmosphere using electical discharges.**Origins of Life and Evolution of the*Biosphere 12: 133-141, 1982.
2.
http://sciam.com/article.cfm?chanID=sa004&articleID=9952573C-E7F2-99DF-32F2928046329479
Then, proteins and nucleic acids can be made spontaneously by heating them either in a dry environment (like an evaporating tidal pool), or at hydrothermal vents:
1. Imai, E., Honda, H., Hatori, K., Brack, A., Matsuno, K. (1999). Elongation of Oligopeptides in a simulated submarine hydrothermal system. Science283: 831-833.
2.
http://serials.cib.unibo.it/cgi-ser...g_art=3523221&language=ITALIANO&view=articoli Synthesizing oligomers from monomeric nucleotides in simulated hydrothermal environments.
Finally, these proteins will spontaneously make living cells when water returns or they move into the cooler water outside a hydrothermal vent:
1.
http://www.theharbinger.org/articles/rel_sci/fox.html
2.
http://www.realmagick.com/sidney-w-fox-microspheres/
14.
http://www.springerlink.com/content/dxq91868368083p2/ pictures of one type of protocell
18.
http://www.biog1105-1106.org/demos/106/unit04/3a.protobionts.html pictures of protocells
These "protocells" metabolize (catabolize and anabolize), grow, respond to stimuli (they have an action potential identical to contemporary nerve cells), and reproduce. Thus, they have all the characteristics that make up "alive".
The reactions are so simple that you can do them in your kitchen:
Call Sigma Chemical Co. at 800-325-3010 and order 1 bottle of catalog number M 7145 and one bottle of R 7131 amino acids solutions (you need both to get all the amino acids
http://www.sigmaaldrich.com/sigma/formulation/M5550for.pdf ). They will cost you about $70 plus shipping for both. Empty the bottles into a fying pan, turn the heat on low and heat until all the water is evaporated. Then heat for 60 more minutes. Add water. You will have protocells in the solution. They are alive. If this is too "artificial" for you, then put the solution out on a hot rock for the afternoon and let it evaporate. Then add water (rain).
Having shown you all this, have I "disproved" God? NO! What I have shown is that your argument (or "proof") for the existence of God is invalid. The existence of God does not depend on His having "poofed" the first living cell into existence. Christian belief is that God uses "secondary causes" things. For instance, God did not directly create
you, did He? No, you arise from a series of secondary causes starting with formation of gametes in your parents, moving through fertilization and embryonic development, and then birth. God does not push the planets around to hold them in orbit around the sun, does He? Instead, He uses the secondary cause of gravity. What I have shown you is the secondary causes that God can create life from non-living chemicals. Please stop using the very bad theology of god-of-the-gaps as "proof". All it does is play into the hands of atheists when the gaps are filled. After all, the corollary is that if God works in the gaps, then God is absent when a gap is filled. You are not helping God or religion.