Russian Orthodox Patriarch Kirill celebrated mass in Tirana on Sunday, the highlight of his first visit to the mainly Muslim Albania.
"We, Orthodox Christians living in various countries, share the same values, and we must follow them," Kirill told hundreds of faithful in Tirana's Orthodox cathedral.
In a country of 2.9 million known for its religious tolerance, Orthodox Christians make up seven percent of the population, behind the 10 percent who are Catholic and the majority Muslims who account for 56 percent, according to the 2011 census.
Kirill, 71, is the spiritual leader of more than half of the world's 250 million Orthodox Christians.
Kirill hailed the Albanian church's "resistance" during a half-century of communist rule, when more than 100 members of the clergy including seven bishops died in detention or were executed for their religious conviction.
More than 1,800 churches were destroyed between 1945 and 1985.
Kirill also praised the "renaissance of faith" the country has seen since the fall of communism in the early 1990s.
"Our Church is marked by the spirit of peaceful coexistence among all religious communities, and the visit by Patriarch Kirill is an affirmation of these values," said Archbishop Anastasios of Tirana, the head of the Albanian Orthodox Church.
Kirill, who arrived in Tirana on Saturday, was to meet Albanian President Ilir Meta and Prime Minister Edi Rama on Monday.
Russian Orthodox Patriarch Kirill hailed the Albanian church's "resistance" during a half-century of communist rule, when dozens of clergy died in detention or were executed and more than 1,800 churches were destroyed