were using the official churches of the Moscow Patriarchate. The appeal of Alexander Solzhenitsyn caused a heated debate, revealing the opposing positions of the disputants. Some completely denied the existence of the Catacomb Church, while others sought to prove the opposite and thereby justify their own position which was irreconcilable with the respect due to the official Church in the USSR (the Moscow Patriarchate). Solzhenitsyn's opinion was not met with sympathy by the leadership of the ROCOR. In 1975, First Hierarch of ROCOR Metropolitan Philaret (Voznesensky) wrote to Solzhenitsyn that not only priests, but also bishops were part of the Catacomb Church. In the 1960s and 1970s, through illegal literature published abroad, and then through samizdat, the concepts of "catacombs" and "catacomb church" returned to the USSR. After that, some authors in the USSR used the word "catacomb" to designate ecclesiastical opposition to the Moscow Patriarchate, while others used it as a technical term as a synonym for the epithet "illegal" from the point of view of Soviet legislation. Since the second half of the 1980s, in connection with the policy of glasnost, the concept of "catacombs" has returned to journalism. References Literature В. Г. Пидгайко. ИСТИННО ПРАВОСЛАВНЫЕ ХРИСТИАНЕ // Православная энциклопедия. — М. : Церковно-научный центр «Православная энциклопедия», 2011. — Т. XXVII. — С. 704-716. , "Роль участников катакомбного движения в организационном оформлении епархий Русской Православной Церкви заграницей на канонической территории Московского Патриархата (1982—1994 гг.)" // Церковно-исторический вестник. 2013—2014. — № 20/21. — С. 218—225 20th-century Eastern Orthodoxy Anti-communist organizations