For Borujerdi the fight against this creed was a top priority, and during the holidays of Ramadan and Moharram he regularly sent his students to the towns and villages to preach against it. As Montazeri had studied the works and writings of the Baha’i, he played an important role in this campaign. When he was sent to Najafabad to agitate against them in 1955, he asked Borujerdi how Muslims should behave towards them. In his response, Borujerdi declared that Muslims should respect the law and maintain peace but that otherwise they should refrain from any contact with Baha’i. Montazeri disseminated this fatwa widely in Najafabad and convinced the representatives of several guilds to sign a declaration that they would no longer serve Baha’i. Thus, drivers refused to take them on their buses and bakers declined to sell them bread. The climate in Najafabad eventually became so hostile that the Baha’i were forced to go into hiding. However, when Montazeri disseminated Borujerdi’s fatwa in Isfahan, the clergy and the people refused to act against the Baha’i. While initially the Shah tolerated the campaign against the Baha’i in return for Borujerdi’s acceptance of his plan to join the Central Treaty Organisation (Cento), which was criticised by the nationalists, he eventually intervened to put a stop to the campaign. Following complaints from Najafabad, Montazeri was summoned by the Isfahani governor, who vowed to put him on trial should he continue his campaign. Although Montazeri threatened to stir up the masses against the Baha’i, he was forced to end his agitation.
Another question that worried the clergy at this time was the increasing influence of the communists. The Tudeh Party, which had been founded in September 1941 after the exile of Reza Shah, was considered by pious Muslims a threat to the traditional order of society due to its openly anti-religious and anti-clerical line. Borujerdi and the traditional clergy condemned the party as an enemy of God, but Montazeri and other politicised clerics took a more moderate position, as they saw it as a potential ally in their fight against the Shah.
The clergy’s position towards the Jebh-e Melli (National Front) led by the landowner and aristocrat Mohammad Mosaddegh (1882– 1967) was marked by the same ambivalence. While most of the clergy kept their distance from his nationalist government when he was elected prime minister in 1951, a small group around the influential politician Ayatollah Abdolqassem Kashani (1882– 1962) actively supported his policies. Kashani notably welcomed the highly popular nationalisation of the Anglo-Iranian Oil Company, and when Mosaddegh was forced to resign in the ensuing conflict he called for a demonstration which significantly contributed to Mosaddegh’s return to power. Montazeri had been introduced to Kashani during a visit to Tehran, and during the following years regularly returned to his house to discuss matters of religion and politics. However, he was careful to keep this contact from being known to Borujerdi who did not approve of clerics engaging in politics. For this reason, Montazeri also declined when the people of Najafabad asked him and Motahhari if they could place them on Kashani’s list for the parliamentary elections.