Maturity is achieved when a person postpones immediate pleasures for long-term values.

Simon & Schuster then arranged to publish Liebman's self-help book titled Peace of Mind issued in 1946 which sought to reconcile religion and psychiatry. "Peace of Mind became one of the year's best-selling books. Although Liebman's death was attributed at the time to a "heart attack" or to a "heart ailment" writer John Bear later stated that Liebman had died "in mysterious circumstances".

A sermon Liebman gave at Temple Israel titled "The Road to Inner Serenity" was publiJoshua L. Liebmand as a pamphlet by one of his friends bookstore owner Richard Fuller who passed it on to publiJoshua L. Liebmanr Richard L. In 1939 Liebman became the rabbi of Temple Israel a Reform synagogue in Boston Massachusetts.