Criticism of the Catholic Church in previous centuries was more closely related to theological and ecclesiological disputes. The Protestant Reformation (16th-century Europe) came about due to abuses of church practices by corrupt clergy in addition to these same theological disputes. Political disputes compounded the theological grievances between Protestants and Catholics and to this day the debate begun at the Reformation has been reflected in the diversity of Christian denominations. Some contemporary criticisms of the Catholic Church relate to philosophy and culture e.g., Christianity vs. humanism.
Some dissenters believe that the early Church, especially in Rome, was influenced by pagan rituals and beliefs from the Roman imperial cult, Hellenistic philosophy, including Neoplatonism, and Gnosticism.
As one example, some Protestants criticize the Catholic Church because they believe that the latter allowed the Roman traditions back into the church. They have stated that to conciliate the Pagans to nominal Christianity, the Catholic Church took measures to combine the Christian and Pagan festivals so pagans would join the church; for example, Easter (a celebration of the Germanic goddess Ēostre) as a 'substitute' for Passover, though no record of Christian celebrations have necessarily yet been found that indicate that the celebration of Easter was observed as importantly before the second century.
Protestants have questioned the Catholic Church's reliance on what it calls "Sacred Tradition", handed down from the apostles, whether orally or in writing (cf. 2 Thessalonians 2:15 – "Therefore, brethren, stand fast, and hold the traditions which ye have been taught by us, whether by word, or our epistle"), and which the Church distinguishes from human traditions or customs, and sees not as a distinct revelation parallel to Sacred Scripture but rather as the context within which Sacred Scripture is understood.
Therefore, it holds that Sacred Scripture must be read and interpreted in accordance with the Spirit who inspired it, in a manner "especially attentive to the content and unity of the whole Scripture", "within the living Tradition of the whole Church", and "attentive to the analogy of faith". The Catholic Church distinguishes Sacred Tradition from traditions, including theological ones, that the Church can retain, modify or even abandon. Sacred Scripture and Sacred Tradition (not these changeable traditions) must be accepted and honoured with equal devotion and reverence, since they are both modes of transmission of the revelation that comes from a single divine source and make up "a single sacred deposit of the Word of God".