He was a heavy drinker, one of the many victims of alcohol. On one occasion he was running about with no clothes on and carrying on as if he were insane.
Our behavior is as absurd and incomprehensible with respect to the first drink as that of an individual with a passion, say for jay-walking. He gets a thrill out of skipping in front of fast-moving vehicles. He enjoys himself for a few years in spite of friendly warnings. Up to this point you would label him as a foolish chap having queer ideas of fun.
Big Book Pgs. 37 & 38
Here is the fellow who has been puzzling you, especially in his lack of control. He does absurd, incredible, tragic things while drinking. He is a real Dr. Jekyll and Mr. Hyde. He is seldom mildly intoxicated. He is always more or less insanely drunk.
Big Book pg. 21
Great Spirit free us from the insanity.