In a statement, Allameh Seyyed Ahmed Shoqi al-Amin said Takfiri groups' attacks against Christians are aimed at harming both Christians and Muslims in Arab and Muslim countries.
He underlined that Takfiri groups have no religion and are enemies of all faiths.
Elsewhere in the statement, Shoqi al-Amin rapped the Zionist regime's atrocities against the Palestinians in the Gaza Strip.
Israeli aggression against the Gaza Strip that has claimed the lives of nearly 1,650 Palestinians since July 8.
Israeli warplanes have been pounding numerous sites in the Gaza Strip over the past days. On July 17, the Israeli military launched a ground offensive against the impoverished Palestinian territory.
Some 9,000 Palestinians have also been injured in the attacks. Most of the casualties have been civilians, including a large number of women and children.