Most studied classics at Harvard from 1968 on and received a B.A. Summa Cum Laude in Classics (Latin) in 1972. He then took a Masters course at Corpus Christi College at Oxford University until 1973, when he continued at the Department of Comparative Literature of Yale University, receiving a M. Phil. in 1978. Two years later, he received a Ph.D. under Paul de Man with a thesis called "The Bait of Falsehood: Studies in the Rhetorical Strategy of Poetic Truth in the Romantic Period". Simultaneously, from 1976 to 1978, he studied classics at the Philologisches Seminar of University of Tübingen and was awarded D.Phil. under Richard Kannicht with a thesis entitled "Pindar's Truth: Unity and Occasionality in the Epinician Ode".
In 1980, Most was appointed Andrew W. Mellon Assistant Professor of Classics at Princeton University and remained in this position until 1985. In 1982/83, he was at the American Academy in Rome. In 1985/86, he taught at the Università degli Studi di Siena, from then until 1987 as visiting professor at the University of Michigan. In 1987, he followed a call from the Universität Innsbruck, becoming Ordentlicher Universitätsprofessor für Klassische Philologie und Altertumskunde. In 1988/89, he was a fellow at the Wissenschaftskolleg zu Berlin. In 1991, Most moved to a full professorship for Ancient Greek language and literature at the Ruprecht-Karls-Universität Heidelberg, where he taught until 2001. During these years, Most also was guest professor at the University of Michigan and professor at the Committee on Social Thought at the University of Chicago. In 1994, Most was the first classicist to receive the Leibniz-Preis of the Deutsche Forschungsgemeinschaft. Since 2001, he is teaching as Professor of Ancient Greek at the Scuola Normale at Pisa.
Most's work ranges from Greek to Latin authors, from literature to philosophy, and from history and methodology of classical studies to modern literary theory and reception history. In particular, he studies the relationship of the modern towards the ancient world, including New Testament topics such as the story of Doubting Thomas.