[3][9] Grossman, looking every inch the Hasidic rabbi with his beard and sidelocks, embarked on a one-man campaign to rehabilitate Sephardi youth immersed in crime and drug use.

[11] In 1972[9][12] Grossman founded the Migdal Ohr (Tower of Light) educational network to give children a loving and caring environment at the age of 6 or 7 so that they could circumvent the cycle of crime and drug abuse that plagued the town's teens and adults.

This program gives over 900[8] inmates, mostly jailed for drug-dealing and armed robbery, the choice to study in a prison kollel on a voluntary basis for three to four hours a day.

[14] Grossman has been offered the position of Chief Rabbi of Israel twice but declined both times in favor of continuing his outreach work in Migdal HaEmek.

[8] During the 2006 Lebanon War, Grossman used his location in the north of Israel to provide services to soldiers suffering from the government’s inefficient handling of troops and supplies.

In one instance, he opened the Migdal Ohr campus to 700 Israeli paratroopers of the IDF Brigade 85 who were stranded in a tank hangar in Petah Tikva, hosting them for swimming, a barbecue and dancing with live Hasidic music.

[9][15] In another case, he let 700 [16] members of the 8th Paratrooper Battalion use Migdal Ohr as their home base during the three weeks of the war, supplying clean clothing, new gear, and use of the recreational facilities.

[15] A preseason exhibition game between the Israeli Maccabi team and the New York Knicks at Madison Square Garden is one of Migdal Ohr's biggest fund-raising events.

Migdal Ohr also relies on substantial funding from foreign governments, nonprofit organizations, and private donors; the United States, among others, demanded that Grossman rescind support for Leifer.

[24] In 2016, Grossman twice appeared before a court in South Africa to negotiate the release from prison of former Shuvu Banim Torah Academy school dean Rabbi Eliezer Berland, who later confessed to rape and assault.

He is the uncle (by marriage) of Rivka Holtzberg, co-director of the Nariman House Chabad center, who was murdered together with her husband Gavriel in the 2008 Mumbai attacks.