Can you point to a qualified and unbiased study which shows pot to be less toxic and more beneficial than alcohol?
Can you point to Church teaching which says that pot must be judged by the same moral theology as alcohol?
You (plural) point to the Church teaching about being "sober." THAT is based on the risks of abuse. I see no mention in 1 Thessalonians 5:7-9 of exceptions, so how exactly does the Church justify ANY use of alcohol? Return to first principles: avoid undue risk of self-harm (whether physically or spiritually).
Since you claim MJ use is different from alcohol use, the burden is on YOU to make the case for the moral or medical difference—on something more substantial than your half-baked [pun-intended] "opinion."
No. I cannot point to "a" single study, but to dozens, even hundreds of studies. Glad you asked.

Start here, my bibliography for a series of 8 articles I wrote about medical marijuana in 2010-2011 when it was an issue in our state:
Important reviewsUniversity of California Center for Medical Cannabis Research—2010 Report to the Legislature
http://www.cmcr.ucsd.edu/images/pdfs/CMCR_REPORT_FEB17.pdf Review on clinical studies with cannabis and cannabinoids 2005-2009. Hazecamp A and Grotenhermen F. Cannabinoids 2010;5(special issue):1-21.
www.cannabis-med.org/data/pdf/en_2010_01_special.pdf Cannabinoids in medicine: A review of their therapeutic potential. Amar MB. Journal of Ethnopharmacology 105 (2006) 1–25.
http://www.ucla.edu.ve/dmedicin/departamentos/fisiologia/cannabinoidsRevPatologias.pdf Emerging Clinical Applications for Cannabis and Cannabinoids: A Review of the Recent Scientific Literature, 2000 – 2010. Armentano P. NORML Foundation, Washington DC 2010.
http://norml.org/pdf_files/NORML_Clinical_Applications_for_Cannabis_and_Cannabinoids.pdf Marijuana and Medicine: Assessing the Science Base. National Academy of Science Institute of Medicine, 1999
http://www.nap.edu/openbook.php?record_id=6376 popularized in: Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=R1 AIDS/HIVUniversity of California Center for Medical Cannabis Research—2010 Report to the Legislature
http://www.cmcr.ucsd.edu/images/pdfs/CMCR_REPORT_FEB17.pdfHuman Immunodeficiency Virus (HIV)
http://www.norml.org/index.cfm?Group_ID=7485 “Marijuana and AIDS” in Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=86 ALS (Amyotrophic Lateral Sclerosis, Lou Gehrig's Disease)Amyotrophic Lateral Sclerosis (ALS)
http://www.norml.org/index.cfm?Group_ID=7004 Alzheimer's DiseaseAlzheimer's Disease
http://norml.org/index.cfm?Group_ID=7003 Cachexia. Wasting syndromeSee sections 3.1 and 3.2 of Cannabinoids in medicine: A review of their therapeutic potential. Amar MB. Journal of Ethnopharmacology 105 (2006) 1–25.
http://www.ucla.edu.ve/dmedicin/departamentos/fisiologia/cannabinoidsRevPatologias.pdf CancerGliomas/Cancer
http://www.norml.org/index.cfm?Group_ID=7008 “Marijuana and Cancer” in Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=95 Cannabis and Cannabinoids (PDQ®). National Cancer Institute. 2011.
http://www.cancer.gov/cancertopics/pdq/cam/cannabis/healthprofessional/page1 Cardiovascular diseaseThe Potential for Clinical Use of Cannabinoids in Treatment
of Cardiovascular Diseases. Durst R and Lotan C. Cardiovascular Therapeutics 2011 Feb;29(1):17-22. doi: 10.1111/j.1755-5922.2010.00233.x. Epub 2010 Oct 14.
http://www.ncbi.nlm.nih.gov/pubmed/20946323 The emerging role of the endocannabinoid system in cardiovascular disease. Pacher P, Steffens S. Semin Immunopathol. 2009 Jun;31(1):63-77. Epub 2009 Apr 9.
http://www.springerlink.com/content/a04103g160h16450/fulltext.pdf Cannabinoid receptors in atherosclerosis. Steffens S, Mach F. Curr Opin Lipidol. 2006 Oct;17(5):519-26.
http://journals.lww.com/co-lipidology/Abstract/2006/10000/Cannabinoid_receptors_in_atherosclerosis.5.aspx Cannabinoid receptors in acute and chronic complications of atherosclerosis. Mach F, Montecucco F, Steffens S. Br J Pharmacol. 2008 January; 153(2): 290–298.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2219535/pdf/0707517a.pdf Endocannabinoids and cannabinoid receptors in ischaemia-reperfusion injury and preconditioning. Pacher P, Haskó G. Br J Pharmacol. 2008 Jan;153(2):252-62. Epub 2007 Nov 19.
http://onlinelibrary.wiley.com/doi/10.1038/sj.bjp.0707582/pdf The role of the endocannabinoid system in atherosclerosis. Mach F, Steffens S. J Neuroendocrinol. 2008 May;20 Suppl 1:53-7.
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2826.2008.01685.x/pdf Cardiovascular Effects of Cannabis | Medicinal Cannabis Information. Independent Drug Monitoring Unit, United Kingdom, undated
http://www.idmu.co.uk/canncardio.htm Crohns DiseaseGastrointestinal Disorders
http://www.norml.org/index.cfm?Group_ID=7009 Endocannabinoid sysytemThe Endocannabinoid System as an Emerging Target of Pharmacotherapy. National Institute of Health: Pacher P, Bátkai S, Kunos G. Pharmacol Rev. 2006 Sep;58(3):389-462.
http://pharmrev.aspetjournals.org/content/58/3/389.full.pdf Endocrine disease, diabetesThe emerging role of the endocannabinoid system in endocrine regulation and energy balance. Pagotto U, Marsicano G, Cota D, Lutz B, Pasquali R. Endocr Rev. 2006 Feb;27(1):73-100. Epub 2005 Nov 23.
http://fk.uwks.ac.id/elib/Arsip/Departemen/Biokimia/The%20Emerging%20Role%20of%20the%20Endocannabinoid%20System.pdf FibromyalgiaNabilone for the Treatment of Pain in Fibromyalgia. Skrabek RQ, Galimova L, Ethans K, Perry D. J Pain. 2008 Feb;9(2):164-73. Epub 2007 Nov 5.
http://docs.google.com/viewer?a=v&q=cache:9gDyCVhqJSMJ:files.meetup.com/404848/2008_Nabilone-for-the-Treatment-of-Pain-in-Fibromyalgia.pdf+Nabilone+for+the+Treatment+of+Pain+in+Fibromyalgia&hl=en&gl=us&pid=bl&srcid=ADGEESjFGavzxEJkBjsOj_YyWPHuo5PRG034PLna8X6n3sXGT696PVuaEH15HF07xVpfV10wLPfon8-nZoD0RcJfU6LInnuqHOGpKDECN4oQ6OWBgGgwXWckH2QB31FTn1BZn0KX9U7A&sig=AHIEtbQlDN8uMzxJIm6KKL0POTJdhmbsvg Delta-9-THC based monotherapy in fibromyalgia patients on experimentally induced pain, axon reflex flare, and pain relief. Schley M, Legler A, Skopp G, Schmelz M, Konrad C, Rukwied R. Curr Med Res Opin. 2006 Jul;22(7):1269-76.
http://www.ncbi.nlm.nih.gov/pubmed/16834825 Fibromyalgia
http://norml.org/index.cfm?Group_ID=7007 GlaucomaAmerican Glaucoma Society position statement: Marijuana and the treatment of glaucoma. American Glaucoma Society, Prepared by Henry Jampel, M.D., M.H.S., August 10, 2009
http://www.americanglaucomasociety.net/associations/5224/files/Marijuana%20and%20Glaucoma%20august%2030_BOD%20Approved%2010.23.09.pdf Marijuana and Glaucoma” in Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=124 Hepatitis CHepatitis C
http://www.norml.org/index.cfm?Group_ID=7010 Marijuana effects, drug levels, DUIMarijuana effect and delta9-tetrahydrocannabinol plasma level. Chiang CWN and Barnett G. Clinical Pharmacology and Therapeutics 1984 Aug;36(2):234-8.
http://www.ncbi.nlm.nih.gov/pubmed/6086207 Contact highs and urinary cannabinoids excretion after passive exposure to marijuana smoke. Cone EJ and Johnson RE. Clinical Pharmacology and Therapeutics 1986 Sep;40(3):247-56.
http://www.ncbi.nlm.nih.gov/pubmed/3017628 Do delta9-tetrahydrocannabinol concentrations indicate recent use in chronic cannabis users? Karschner EL, Schwilke EW, Lowe RH, Darwin WD, Pope HG, Herning R, Cadet JL, Huestis MA. Addiction. 2009 Dec;104(12):2041-8. Epub 2009 Oct 5.
http://www.clinchem.org/cgi/reprint/49/7/1114 Developing limits for driving under cannabis. Grotenhermen F, Leson G, Berghaus G, Drummer OH, Krüger HP, Longo M, Moskowitz H, Perrine B, Ramaekers JG, Smiley A, Tunbridge R. Addiction 2007 Dec;102(12):1910-7. Epub 2007 Oct 4.
http://www.ncbi.nlm.nih.gov/pubmed/17916224 Urinary cannabinoid detection times after controlled oral administration of delta9-tetrahydrocannabinol to humans. Gustafson RA, Levine B, Stout PR, Klette KL, George MP, Moolchan ET, Huestis MA. Clin Chem. 2003 Jul;49(7):1114-24.
http://www.ncbi.nlm.nih.gov/pubmed/12816908 Editorial: Practical Challenges to Positive Drug Tests for Marijuana. ElSohly MA. Clin Chem. 2003 Jul;49(7):1037-8.
http://www.clinchem.org/cgi/reprint/49/7/1037 Dose related risk of motor vehicle crashes after cannabis use. Ramaekers JG, Berghaus G, van Laar M, Drummer OH. Drug Alcohol Depend. 2004 Feb 7;73(2):109-19.
http://www.ukcia.org/research/DoseRelatedRiskOfCrashes.pdf Tolerance and cross-tolerance to neurocognitive effects of THC and alcohol in heavy cannabis users. Ramaekers JG, Theunissen EL, de Brouwer M, Toennes SW, Moeller MR, Kauert G. Psychopharmacology (Berl). 2011 Mar;214(2):391-401. Epub 2010 Oct 30.
http://www.cannabistherapyinstitute.com/bills/dui/raemakers.etal.pdf Cannabis and Driving: A Scientific and Rational Review. Armentano P. NORML Foundation, Washington DC 2010
http://norml.org/index.cfm?Group_ID=7459 Sex differences in the effects of marijuana on simulated driving performance. Anderson BM, Rizzo M, Block RI, Pearlson GD, O'Leary DS. J Psychoactive Drugs. 2010 Mar;42(1):19-30.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3033009/ Effects of THC on driving performance, physiological state and subjective feelings relative to alcohol. Ronen A, Gershon P, Drobiner H, Rabinovich A, Bar-Hamburger R, Mechoulam R, Cassuto Y, Shinar D. Accid Anal Prev. 2008 May;40(3):926-34. Epub 2007 Nov 26.
http://www.ncbi.nlm.nih.gov/pubmed/18460360 Muscle SpasmsDystonia
http://www.norml.org/index.cfm?Group_ID=7006 “Marijuana and Muscle Spasticity” in Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=106 NauseaSee sections 3.1 of Cannabinoids in medicine: A review of their therapeutic potential. Amar MB. Journal of Ethnopharmacology 105 (2006) 1–25.
http://www.ucla.edu.ve/dmedicin/departamentos/fisiologia/cannabinoidsRevPatologias.pdf PainUniversity of California Center for Medical Cannabis Research—2010 Report to the Legislature
http://www.cmcr.ucsd.edu/images/pdfs/CMCR_REPORT_FEB17.pdfChronic Pain
http://www.norml.org/index.cfm?Group_ID=7786 “Marijuana and Pain” in Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=77# Post traumatic Stress DisorderCannabinoid receptor activation in the basolateral amygdala blocks the effects of stress on the conditioning and extinction of inhibitory avoidance. Ganon-Elazar E, Akirav I. J Neurosci. 2009 Sep 9;29(36):11078-88.
http://www.jneurosci.org/content/29/36/11078.full.pdf+html [Extinction of emotional response as a novel approach of pharmacotherapy of anxiety disorders]. Lehner M, Wisłowska-Stanek A, Płaznik A. Psychiatr Pol. 2009 Nov-Dec;43(6):639-53.
http://www.ncbi.nlm.nih.gov/pubmed/20209877 The Use of a Synthetic Cannabinoid in the Management of Treatment‐Resistant Nightmares in Posttraumatic Stress Disorder (PTSD). Fraser GA. CNS Neurosci Ther. 2009 Winter;15(1):84-8.
http://onlinelibrary.wiley.com/doi/10.1111/j.1755-5949.2008.00071.x/pdf Public policyHarm reduction-the cannabis paradox. Melamede R. Harm Reduct J. 2005 Sep 22;2:17.
http://www.harmreductionjournal.com/content/pdf/1477-7517-2-17.pdf Seizures
See sections 3.7 of Cannabinoids in medicine: A review of their therapeutic potential. Amar MB. Journal of Ethnopharmacology 105 (2006) 1–25.
http://www.ucla.edu.ve/dmedicin/departamentos/fisiologia/cannabinoidsRevPatologias.pdf “Marijuana and Neurological Disorders” in Marijuana As Medicine? – The Science Behind the Controversy. Mack A and Joy J. National Academy of Science. National Academy Press, Washington DC 2000.
http://books.nap.edu/openbook.php?record_id=9586&page=115