In sociology, secularization (or secularisation) is a multilayered concept that generally denotes "a transition from a religious to a more worldly level." Most versions of secularization do not lead to atheism, irreligion, nor are they automatically anti-thetical to religion. Secularization has different connotations such as implying differentiation of secular from religious domains, the marginalization of religion in those domains, or it may also entail the transformation of religion as a result of its recharacterization (e.g. as a private concern, or as a non-political matter).
Secularism's origins can be traced to the Bible itself and fleshed out through Christian history into the modern era. "Secular" has been a part of the Christian church's history, which even had secular clergy in the medieval period. Furthermore, secular and religious entities were not separated in the medieval period, but coexisted and interacted naturally. "Secular" has been a part of the Christian church's history, which even had secular clergy in the medieval period. Significant contributions to principles used in modern secularism came from prominent theologians and Christian writers such as St. Augustine, William of Ockham, Marsilius of Padua, Martin Luther, Roger Williams, and John Locke.
The term "secularization" can mean the lifting of monastic restrictions from a member of the clergy, and to deconsecration, removing the consecration of a religious building so that it may be used for other purposes. The first use of "secular" as a change from religion to the mundane is from the 16th century that referred to transforming ecclesiastical possessions for civil purposes, such as monasteries to hospitals; and by the 19th century it gained traction as a political object of secularist movements. In the 20th century, "secularization" had diversified into various versions in light of the diversity of experiences from different cultures and institutions.