His recordings include four volumes of works by students of Franz Schreker in his master classes in Vienna and Berlin.
Lessing has performed worldwide as a violinist and pianist, also giving musicological lectures and master classes at European and North American universities.
[2][3] Lessing has dedicated to wide-ranging repertoire, with a focus on works by composers who were ostracised under the Nazi regime, including Franz Schreker and his circle of students.
[4] He revived stylistically different compositions for solo violin by Haim Alexander, Tzvi Avni, Abel Ehrlich, Jacqueline Fontyn, David Paul Graham, Ursula Mamlok, Krzysztof Meyer, Klaus Hinrich Stahmer, Hans Vogt.
As a violinist and a pianist, he premiered compositions including the piano concerto Rivages solitaires by Jacqueline Fontyn, Rudolf Hindemith's Suite, Ignace Strasfogel's A Child's Day, the violin concertos by Haim Alexander, Sidney Corbett's Yael, works by Abel Ehrlich and Stefan Hippe, Zoltán Székely's Allegro, A une Madone by Dimitri Terzakis, and Le Violon de la Mort by Grete von Zieritz.