This article aims to determine the evolution of the national security clause as a legal ground for the dissolution of religious organisations, in particular, the Russian Orthodox Church in Ukraine (ROCU) in Ukraine. The assessment is conducted through the prism of Art. 9 and Art.11 of the ECHR and purports to establish the conformity of the Ukrainian legislature with the ECHR. Apart from that, the article elaborates on the interplay between emergency law, martial law, and legislative amendments concerning the status of the Church. I argue that the ROCU matter has been securitised in two stages. Firstly, during the presidency of the fifth President of Ukraine, in 2018-2019, when the Ukrainian independent church was created under “national identity” and “national security” slogans. Later, in the aftermath of the Russian invasion of Ukraine in 2022 when, a spark of investigations showing collaboration between some representatives of the ROCU and Russia led to the weaponisation of the ROCU. Consequently, the national legislature has been amended to reflect on these issues. I submit that the Russian invasion of Ukraine in 2022 allowed the introduction of martial law as an emergency regime, under which Ukraine was able to derogate from major human rights instruments, including ECHR. Derogations allowed Ukraine to expand its margin of appreciation. However, the ECHR can exercise post-factum control on the measures taken in times of emergency. I believe that prohibiting the ROCU’s activities by legislative act will result in grave interference under the ECHR. Additionally, such a prohibition can fail to meet the requirements of the proportionality test, considering the current Ukrainian legislature. Also, the legislative changes raise the matter of attribution between the representatives of the ROCU and the ROCU as a religious organisation.