In 1874, Rev. Mendes became Minister of the newly formed Sephardic congregation in Manchester, England. In 1877, he was called to the Congregation Shearith Israel of New York where he served for 60 years until his death in 1937. As his successor, Rabbi David de Sola Pool, describes it: "The Rev. Jacques Judah Lyons, the venerable hazan of the congregation, was failing in health, and he passed away on August 13, when Dr. Mendes had been installed for only two and a half months. It was no easy task for the young preacher from abroad to fill the void created by the death of Mr. Lyons, who was bound to the congregation by almost forty years....But Dr. Mendes loyally continued the traditions....It is impossible to record the untiring affectionate personal service which Dr. Mendes at all times gave to the members of his congregation in joy and in sorrow...an inspiration to the bride and bridegroom under the canopy, and a stay of strength to those stricken by bereavement. He was a spiritual father to two generations in his congregation. However occupied or weary he might be, no call ever found him other than ready to respond.” In addition, to synagogue duties, Rev. Mendes served as professor of homiletics at Yeshiva Isaac Elchanan from 1917 to 1920.
Musical contributions
Rev. Mendes also made musical contributions to the congregation. As Jewish music scholar Neil W. Levin explains: "Mendes also composed settings for the hazzan and choir of Shearith Israel, judiciously retaining the stylistic continuity of the Amsterdam Sephardi musical tradition and preserving its unique aura and melodic character, and some of these settings earned a place in the congregation’s permanent standard repertoire. Such is the case with his setting of uv’nukho yomar, sung to this day at the conclusion of the Torah service after the Torah scrolls have been replaced in the ark, and his setting of Psalm 23."
Shooting
On March 5, 1892, he was shot in the abdomen at his home by a beggar named Jose Mizrachee, narrowly escaping with his life. Years later, at the man's passing, Dr. Mendes paid for his funeral and ensuring a proper Jewish burial.
Organizational activities
During his long career, Dr. Mendes participated in the establishment of a number of organizations for the betterment of both Jews and non-Jews:
New York Board of Ministers - In 1881, he was one of the founders of the New York Board of Ministers and acted as its secretary from its foundation up to 1901 when he became president.
Jewish Theological Seminary - In 1886, Rev. Mendes joined Sabato Morais in helping to establish the Jewish Theological Seminary, of which he became secretary of the advisory board and professor of history. On the death of Dr. Morais, he became acting president of the faculty until the appointment of Solomon Schechter in 1902.
Montefiore Home - In 1884, the centennial of the birth of Sir Moses Montefiore, Rev. Mendes moved his congregation to convene the leading Jews of New York to mark the event by some practical work. The outcome was the Montefiore Home for Chronic Invalids, established in the same year.
Guild for Crippled Children - In 1896, he was made vice-president of the Guild for Crippled Children, and in 1901 established the Jewish branch of that guild.
Rev. Mendes was an ardent voice in the striving for a Jewish homeland. He was asked by Theodore Herzl to spread the Zionist cause in America and became one of the founders of the Federation of American Zionists, serving as Vice-President. He was also a member of the Actions Committee of Vienna. Following are some of his writings on the issue:
"The Solution of Zionism," The North American Review, 1 Aug 1895 https://archive.org/details/jstor-25103563
"Zionism," The North American Review, 1 Jan 1897 https://archive.org/details/jstor-25119049
"The Zionist Conference in Basle, Notes and Comments," The North American Review, 1 Nov 1898 https://archive.org/details/jstor-25119100
"The Hague Conference and Palestine," The North American Review, 7 Sept 1906 https://archive.org/details/jstor-25105623
"The Rejuvenation of the Jew," The North American Review, 1 Jan 1897 https://archive.org/details/jstor-25118900
Books and articles
Rev. Mendes authored books on a wide range of topics: Judaism, history, current affairs, and even fiction -- always with an ethical message. In addition, he was a prolific contributor to various journals. Together with his brother Frederick de Sola Mendes and others, he was one of the founders of "The American Hebrew". He wrote as well for the North American Review. Following is a partial list of his writings:
The Jewish Religion, Ethically Presented https://archive.org/details/jewishreligionet00mendiala
Jewish Daily Life, Ethically Presented
Bar-Mitzvah for Boyhood, Youth and Manhood
History and Current Affairs
"The Lifting of the Veil: Introductory Lecture on Jewish History and Literature," 1898 https://archive.org/details/liftingofveilint00mendiala
"Looking Ahead: 20th Century Happenings" https://archive.org/details/lookingaheadtwen00mend
Fiction
The Earl of Beaconsfield, Keys to the Famous Characters https://archive.org/details/TheEarlOfBeaconsfield
Esther and Harbonah https://archive.org/details/estherharbonah00mend
In Old Egypt: A Story about the Bible but not in the Bible
Judas Maccabaeus: A Chanuka play for Sunday school children, 1898
Death
Rabbi Mendes continued to be active as an author and orator in his later years, and was in good health until suffering a heart attack a week before his death. He died in his home in Mount Vernon, New York on October 20, 1937 and was buried in Beth Olam Cemetery in Cypress Hills, Queens.
