Described as having "brilliant style and […] extensive theoretical and practical knowledge,"[1] Bekker was chief music critic for both the Frankfurter Zeitung (1911–1923), and later the New Yorker Staats-Zeitung (1934–1937).

[3] After Bekker stopped professional performance he began music criticism, publishing monographs on Oskar Fried (1906/7) and Jacques Offenbach (1909), as well as a successful book on Beethoven in 1911.

[3] In his 1918 work Die Sinfonie von Beethoven bis Mahler, Bekker developed the idea that symphony had a "community-building force" (gemeinschaftbildende Kraft).

[6] Bekker fled Germany for Paris after Hitler's rise to power, and emigrated to New York in 1934, becoming chief music critic of the New Yorker Staats-Zeitung.

[1][2] Bekker married three times: to Dora Zelle between 1909 and 1920, to Hanna vom Rath between 1920 and 1930, and to Margit Reinhard from 1935 until his death.