Abraham Feinberg (14 September 1899 – 5 October 1986) was an American rabbi who lived much of his life in Canada. In his obituary, The New York Times declared about him: "He was always ready to march, lend his name or send a telegram if there was a protest for disarmament or for a treaty on a nuclear test ban, or against racism in South Africa, radical injustice in America and United States policy in Vietnam."

From rabbi to pop star Feinberg was born in Bellaire, Ohio, to Yiddish-speaking Ashkenazi-Jewish parents, immigrants from Grinkishki (modern Grinkiškis, Lithuania) in the Russian empire. Feinberg always called Grinkishki "the birthplace of my spirit". His parents often spoke to him about the shetl that they had left behind, and Feinberg stated that he felt that Grinkishki was a part of him. His father, Nathan was a rabbi, while his mother, Sarah (née Abramson) was a housewife. Another source describes Nathan Feinberg as a cantor and umbrella repair man who left the Russian empire for the United States. In his memoirs, Feinberg stated his parents moved to the United States in 1882. Feinberg was the 7th of the 10 children in his family.

Bellaire was an impoverished coal-mining town located on the Ohio river across from Wheeling, West Virginia and Feinberg grew up in poverty. Feinberg found himself shocked by the mistreatment of the black residents of Bellaire when he was growing up. One day, he saw a young black boy known as Skeets being pelted with stones and garbage on the streets. When Skeets attempted to swim across the Ohio to escape his tormentors, he was hit on the head by a rock and drowned. Since Skeets was black, his death was written off by the authorities as of no importance. Feinberg's best friend as a child was Dude, the son of a black garbageman. His childhood experiences left him with a strong sympathy for Afro-Americans as fellow victims of prejudice, and throughout his life he was a champion of civil rights. An intellectual prodigy, Feinberg graduated from high school at the age of 14. After graduating, he went to work as a menial laborer while saving up enough money to attend university. Feinberg worked in a steel mill in Bellaire. Bellaire was a tough working class town where violence and heavy drinking were the norm, and Feinberg was hardened by his youth. Feinberg recalled about his youth: "Passion for the underdog still stirs me to indignation. I saw coal miners beaten on the streets because they demanded an union; I saw a black playmate drowned ... stunned by rock-throwing rednecks yelling 'nigger!'"

He was educated at the University of Cincinnati, where he earned a Bachelor of Arts degree in 1920. In 1924, he was ordained a rabbi at the Hebrew Union College in Cincinnati. Feinberg worked as a rabbi in a number of American cities between 1924 and 1930. Feinberg began his rabbinical career at Temple Beth-El in Niagara Falls, New York. In 1925, he moved to Wheeling to become the rabbi of Eoff Street Temple.

In 1928, Feinberg became the rabbi at a New York synagogue, the Temple Israel, attended by a wealthy congregation, and he often went to parties and dinners hosted by New York's Jewish elite on exclusive Park Avenue. Temple Israel was the second largest Reform synagogue in New York. By his own admission, he found himself bored by the superficiality of upper-class life in New York, and found himself yearning for something more in life than attending one party after another. In 1964, Feinberg recalled: "Full of youthful idealism, I found myself increasingly disillusioned with the role I was expected to play—more a promoter and social director of a complex organization than a pastor of human souls".

On 27 February 1930, he announced in a sermon his resignation as a rabbi, saying: "The preacher today has been forced to renounce his mission and become a salesman. He is made to fear a loss in membership more than the wrath of God. Instead of a poet, a dreamer, a transcendent mystic, he distorts himself into a seeker after popularity, a clerk of pew rentals, a good fellow. Just as other men sell clothes or automobiles or stocks, so does he dispense religion—for a price". In his sermon "Why I am Leaving the Professional Ministry", Feinberg stated "organized religion is a deserted lighthouse" that had left him spiritually numb.

His resignation from a prestigious synagogue attended by some of the richest Jews in New York attracted much publicity at the time. In Moscow, Pravda put his resignation on the front page, portraying Feinberg's resignation as due to the soullessness of American capitalism in New York, though Feinberg insisted he was only rejecting organized religion, not Judaism as a faith. Joseph L. Lewis, president of the Freethinkers of America, invited Feinberg to join him on a "crusade for truth" against all religion, an offer he declined. Heywood Broun praised Feinberg's resignation as an act of principle. Two columns of newsprint in The New York Times were devoted to discussing Feinberg's resignation. Rabbi Jacob Kohn of New York's Temple Ansche Chesed called Feinberg a "young and immature, disillusioned idealist". Rabbi Kohn went on to say: "Rabbi Feinberg is an idealist, and his remarks were those of an idealist, and when he refers to commercialism in organized religion, his remarks are the remarks of the disillusioned idealist. He was premature. He should have remembered that it is not fair to condemn the religious institution as a whole because some human errors had upset his inspiration. It would be just as unfair to condemn the entire judicial system of a nation because one magistrate had yielded to corruption."

Feinberg then went to France, where he studied singing at the American Conservatory at Fontainebleau for a few months. Upon his return to New York, he announced his intention to have a career in show business. On November 4, 1930, he married Ruth E. Katsh in New York. Feinberg sang under the Gentile-sounding stage name Anthony Frome. From 1932 to 1935, he hosted a popular radio music show in New York, where he was known as the "Poet Prince of the Air Waves". Feinberg's radio career began at WMCA radio station, but he was soon promoted up to WOR, a station with a more powerful radio broadcaster that covered much of the northeast of the United States. By 1932, Feinberg was being paid $1, 500 dollars per week, a substantial sum in the Great Depression.

Feinberg believed that much of the success of his radio show was due to the fact that starting in 1933 it always aired right after President Franklin D. Roosevelt gave his weekly "fireside chats" on the radio. His persona was that of a "vagabond prince" who would "visit" a different country every radio show and sing love songs in whatever language of the nation he was pretending to visit (Feinberg was fluent in six languages). Feinberg was described as having a "melodious baritone" voice. Feinberg's mother disapproved of his change of career, telling her son on her deathbed in Yiddish: "Abelch, mein zoon, a rov, a rov! Yetzt gevoren a zinger, a gornit!" ("Abe, my son, a rabbi, a rabbi! Now's he become a singer, a nothing!").

Feinberg as Frome was photographed dressed in an expensive smoking robe and slippers in what the newspapers called "his 40-foot living room, lined with portraits in oil and precious first editions", giving the impression of a man who lived a life of decadence and luxury. In his 1964 memoir Storm the Gates of Jericho, Feinberg recalled that his image was remade as follows: "One NBC publicity luminary disagreed with the 'singing rabbi' approach. 'What female in Omaha or Patchogue would weave her fantasy sex-fulfillment around a rabbi?' he demanded. 'They think of a rabbi as an old man with a long beard!' So this unromantic image must be countered by letting the fans see what I looked like. Soon a photograph streamed from the publicity mill—wavy-haired, broodingly dark but serenely poetic, in dressing gown, smoking a pipe and reading in the library of his palatial apartment."

Newspapers stories in the 1930s portrayed him as an eccentric who never sang without the Rubaiyat of Omar Khayyám in his pocket, that he spent vast sums of money on buying clothing, that he was planning to build a castle in the Berkshires, and that he had an obsession with barrel organs. A handsome man, Feinberg appeared on the cover of Radio Guide and was labelled "a romantic idealist" who was looking the world over for the right girl to marry. The fact that Feinberg was already married was kept a secret to make him more appealing to his female fans. A fan club consisting mostly of young women known as the "court of the poet prince" emerged, and Feinberg sang at New York's Fox and Paramount Theaters. He noted with amusement that his fans, unaware that he was Jewish, always sent him Christmas cards. Feinberg recalled about his singing career: "My repertoire ran the gamut from the products of flash-in-the-pan tunesters who were pounding out romance for Bing Crosby and Rudy Vallee, to Victor Herbert and Stephen Foster: from Richard Rodgers, Jerome Kern, Cole Porter and Noël Coward to Schubert, Puccini and Verdi: from Valentina, Siboney, La Cucaracha and The Night Was Made for Love to The Rosary and Kol Nidrei, from tender lullabies to sombre lyrics of passion in every tongue. But always it must be "from person to person, from heart to heart.” I faced the cold metallic microphone and tried to concentrate on somebody I loved — Mom or Ruth, depending on the type of love I was trying to project".

Tikkun olam: the activist rabbi By 1935, he was sufficiently troubled by Nazi Germany to end his career as a singer and returned to working as a rabbi. Feinberg later stated that in view of what was happening in Germany that he could not be a singer and had to return to the service of God. Feinberg stated in 1950 about his return to religion: "I began thinking about what was going to happen to the Jews and I knew that there was only one thing for me to do—I had to go back to the rabbinate. That was, and is, where I belong. Singing is only amusement. My soul is in the pulpit and in the study." In 1935, he became the rabbi of Mount Neboh Temple, a small synagogue located in a poor neighborhood of New York. Mount Nehob was so poor the synagogue had been lacking a rabbi for some time as most rabbis did not wish to accept the low salary the synagogue offered, but Feinberg accepted the position as he wanted to be close to the poor. Feinberg's principal worry was the Third Reich, and from 1935 onward, he sought to build alliances outside of the Jewish community to rally a front against the Nazi regime. In 1938, he moved to Denver, Colorado to become the rabbi of Temple Emanuel. In 1942, Feinberg attempted to volunteer as a chaplain with the U.S. Army, but was turned down on the account of a medical disability."

In 1943, he accepted an offer to become the rabbi at Holy Blossom Temple in Toronto, the most prestigious Reform synagogue in Canada. Feinberg arrived in Toronto in November 1943. By that time, the 1st Canadian Corps was fighting in Italy, and he later remembered that he arrived to find a nation that was engrossed in the war. Through the full dimensions of the "Final Solution to the Jewish Question" were not known in North America at the time, Feinberg knew enough about what was happening to the Jews of Europe. He was an enthusiastic supporter of the war, urging Canadians to never slacken in the war against the 3rd Reich, and urged able-bodied Jewish men to enlist in the military as "active" members.