The Chofetz Chaim was a modest and humble man. He served as the town rabbi of Radin for a short period. His distaste of the pulpit rabbinate led him to resign from this position. For a while he had a shop selling household provisions, which his wife managed while he supervised the absolute accuracy of the weights and measures, the quality of the merchandise, and the fairness of the prices, to make certain that no one was deceived or overcharged in any way. He spent his days learning Torah and disseminating his knowledge to the common people. He later turned to teaching in order to support himself and his family. From 1864 to 1869 he taught Talmud in Minsk and Washilishok. In 1869, he organized a Yeshiva in Radin. The Yeshiva was a success and grew to world famous prominence. It later became known as "Yeshivas Chofetz Chaim of Radin."

In addition to spreading Torah through his yeshiva, the Chofetz Chaim was very active in Jewish causes. He traveled extensively to encourage the keeping of the Mitzvos amongst Jews, totally disregarding his . He became one of the most influential rabbis within Orthodox Judaism during the late 19th and early 20th century, taking a central leadership role in the World Agudath Israel movement in Eastern Europe.

The Chofetz Chaim authored dozens of Seforim, all which have been printed and disseminated by the tens of thousands. Most widely acclaimed is his Mishna Berurah, a six volume comprehensive commentary on Shulchan Aruch Orach Chaim which has become the final arbiter in Halacha. His first book, (published in 1873), deals with the Biblical laws of gossip and slander and which in recent decades has gained worldwide popularity.

The Chofetz Chaim was a tremendous supporter of the Jewish community in Israel and a dear friend and admirer of Rabbi Shmuel Salant, the Chief Rabbi of Jerusalem. The Chofetz Chaim wielded tremendous influence, particularly in Europe and he used that authority to assist Rabbi Salant in maintaining the viability of Jewish settlement in Israel and its funding via the Rabbi Meir Baal Haneis Salant charity fund.

The Chofetz Chaim passed away in 1933 at the age of 95. He was mourned by the entire Jewish world. Even the gentile world had held him in the greatest esteem. The New York Times of September 16, 1933 wrote a lengthy obituary lauding this legendary leader of world Jewry. Times magazine in its September 25, 1933 issue also published a brief but notable obituary as quoted here: