Eastern Orthodox Church

Orthodox theology is based on a sacred tradition that includes the dogmatic decrees of the seven ecumenical councils, Scripture, and the teaching of the Church Fathers.

An excerpt from the article 18 facts about Eastern Orthodox Church

The Orthodox Church teaches that it is the one holy and apostolic Church established by Jesus Christ and that its bishops are the successors of Christ's apostles.

It maintains that it practices the original Christian faith as handed down by sacred tradition.