A ruling by the Council of State that was made public on Friday deemed as unconstitutional reforms to religion classes at schools introduced by the previous leftist government in 2017.
In its ruling, the country's highest administrative court deemed that the reforms by the SYRIZA government relating to the teaching of religion in primary and secondary schools violated not only the Greek constitution but also European human rights treaties.
In its reasoning, the court said that religious affairs classes "should seek to develop the Orthodoox Christian conscience and that this lesson should be directed exclusively at Orthodox Christian pupils."
Pupils who have other faiths or are atheist should have the right not to follow those classes and should not be obliged to do so, the ruling said, adding that the pupils in question can submit a written request to be excused. In the event that a sufficient number of pupils forgo those classes, the state is obliged to hold a different class for them during that time slot, it said.
As for the religion classes introduced during the previous government, the court deemed that "their goal and content does not aspire to the development of pupils' Orthodox Christian conscience" and does not comprise "a comprehensive... teaching of the dogmas, moral values and traditions of the Orthodox church."
In a separate ruling, the court found that the practice of Greek schools publishing the religious faith and nationality of pupils on school certificates is also unconstitutional.
Education Minister Niki Kerameus earlier in the day signed a ministerial decision ending that practice.