Pope Francis described the Jewish people as the “big brothers” of his Roman Catholic flock on Sunday in words of solidarity marking the 75th anniversary of the Kristallnacht attacks on Jews and their property in Nazi Germany.

Francis said the state-sponsored ransacking of Jewish homes, businesses and synagogues, on the night of Nov. 9, 1938, in which scores of Jewish people were killed, marked a step towards the Holocaust and should not be forgotten.

“We renew our closeness and solidarity to the Jewish people, our big brothers, and pray to God that the memory of the past and of the sins of the past helps us to be always vigilant against every form of hate and intolerance,” Francis told thousands in St. Peter’s Square in his Sunday mass.

The leader of the Roman Catholic Church has pledged good relations with Jews and his March election was welcomed by the world’s Jewish associations.

Francis co-authored a book on inter-faith dialogue with Argentine Rabbi Abraham Skorka while he was Archbishop of Buenos Aires.