He was a volunteer spear carrier and prop boy at the New York Metropolitan Opera as a teenager, and he had classical training as a singer.
From 1958 to 1963, he was an assistant instructor and doctoral student in English at Ohio State University, where he was informally mentored by John Crowe Ransom of nearby Kenyon College.
During this period, Ransom recommended Kessler for a Robert Frost Fellowship in poetry at the Bread Loaf Writers' Conference in the summer of 1961.
Paglia later wrote that the biggest impact on her thinking were the classes taught by Kessler: The way I was trained to read literature by Milton Kessler, who was a student of Theodore Roethke, he believed in the responsiveness of the body, and of the activation of the senses to literature.
Boarding a bus after a visit to Binghamton, Blackburn told Kessler, "How warm to share a common disease."