This tribute examines the life and contributions of Professor Mordecai M. Kaplan on his ninetieth birthday, drawing on sixty-two years of personal observation by the author. The study employs biographical methodology and rabbinical textual analysis to assess Kaplan's scholarly achievements and pedagogical influence. The analysis reveals Kaplan's exceptional early promise when appointed professor of homiletics at the Jewish Theological Seminary at age twenty-nine, his pioneering role in establishing the Seminary's Teachers' Institute, and his evolution from Orthodox rabbi to innovative Jewish philosopher. The research documents Kaplan's transition from serving Orthodox congregations to developing new theological frameworks for American Jewish life, despite facing significant opposition. Key findings demonstrate Kaplan's sustained intellectual vitality, evidenced by his continued proposals for Jewish religious innovation even at age ninety, including initiatives for Sabbath home observance and restoration of the tekhelet prayer thread. The study concludes that Kaplan's significance transcends theological agreement or disagreement, establishing him as a transformative figure who combined scholarly rigor with compassionate leadership. His legacy embodies the rabbinical ideal of possessing both youthful vigor and elderly wisdom throughout his career, positioning him as a "comforter to his people" who demonstrated possibilities for Jewish religious and cultural renewal in America.