I could not find a M. P. Ray as a Missouri Confederate, but found one in Arkansas

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Moses P. Ray, Private, Company C, 14th (Powers’) Arkansas Infantry, enlisted July 11, 1861 in Yellville by E. W. Turner for 12 months, on sick furlough February 10, 1862 remaining absent through August, 1862, subsequently dropped from the rolls and reported as deserted June 6, 1862, notation on one card Marion County, Ark.

M317: Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Arkansas

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Moses Patric Ray91,92, born 22 December 1815 in Warren Co., KY; died 25 July 1889 in Boone Co., AR; married Ruth Ann Froshour 19 September 1841 in Evansville, Washington Co., AR; born 28 August 1824 in TN.
Notes for Moses Patric Ray:
SOURCE: Ballenger, Jerry. 'Confederate Soldiers Descended From Joseph M. Ray'
'Moses [son] was already 45 years old when he enlisted on July 11, 1861 at his home in Yellville, Arkansas in C Company, 14th Arkansas Infantry. In August, when his nephew, James H. Ray, was fighting the Battle at Oak Hill, the regiment was still at Yellville. On August 22nd, the 14th was the subject of some correspondence among the top brass. It was reported that General Hardee, commanding in northern Arkansas, " does not wish to receive it." But by October, the regiment was under the command of General Ben McCulloch, as was the 3rd Texas Cavalry. Since James H. Ray spent the winter of 1861-1862 in winter quarters in Arkansas, it is quite possible that James and Moses had contact with each other. [I have not yet discovered exactly where Moses' regiment wintered.]
On February 10, 1862, Moses was placed on sick furlough. It has been reported that he attempted to re-join the regiment, but was unable to locate it. That would be entirely understandable. It early March, the army had been involved in the Elkhorn Tavern battle and shortly thereafter began its march to Corinth, Mississippi; but only General Van Dorn had known where they were going. Moses was carried on the company rolls until June 6, 1862, when he was dropped as a deserter.
A skirmish took place in Yellville on June 25 1862 [Another incident took place there on November 11-12, 1864.] It could well have been that you didn't have to leave town to fight Yankees!

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