Despite the difficulties imposed by the socialist regime first, and then during the military dictatorship, Kreiman started religious equalitarian services, youth activities, summer camps, conferences, and cultural events even amidst protests.
During the dictatorship, he worked hard to support human rights; he was a founding member of the Committee of Cooperation for Peace in Chile (Comité Pro Paz), a human rights organization created in 1973 by the Christian churches together with the Jewish community to protect the life and physical integrity of people persecuted by the military dictatorship of Chile.
In 1994, a powerful bomb shattered the AMIA building (Asociación Israelita Argentina) in Buenos Aires.[4]).
[2] In 2012, Rabbi Kreiman made Aliyah where he settled in Jerusalem, a couple of blocks away from the Great Synagogue, where he was admired and acknowledged for his presence, knowledge of the liturgy and the ability to create bonds.
Kreiman was close to Opus Dei, and participated in congresses in Buenos Aires and at the Pontifical University of the Holy Cross in Rome.
[5] Notably, in 1998 he was invited by King Hussein of Jordan, who warmly welcomed him as an honored guest, facilitating the commencement of the Judeo-Islamic dialogue in Latin America.