Sentence:  In the dimness of the landing I could not see him very well, but there was something in his voice that surprised me. I knew he was of <WSD>abstemious</WSD> habit or I should have thought he had been drinking. 
Meaning of the word marked with <WSD> tags:  Refraining from freely consuming food or strong drink; sparing in diet; abstinent, temperate. (From early 17th c.)