In Cynicism "adiaphora" represents indifference to the vicissitudes of life. In Pyrrhonism, "adiaphora" indicates things which cannot be logically differentiated. Unlike in Stoicism, the term has no specific connection to morality. In Stoicism "adiaphora" indicates actions that morality neither mandates nor forbids. In the context of Stoicism "adiaphora" is usually translated as "indifferents."
In Christianity, "adiaphora" are matters not regarded as essential to faith, but nevertheless as permissible for Christians or allowed in church. What is specifically considered adiaphora depends on the specific theology in view.
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The Cynics cultivate adiaphora, by which they meant indifference to the vicissitudes of life, through ascetic practices which help one become free from influences – such as wealth, fame, and power – that have no value in nature. Examples include Diogenes' practice of living in a tub and walking barefoot in winter.
Aristotle uses "adiaphora" to mean "undifferentiated by a logical differentia." 
Pyrrho claimed that all pragmata (matters, affairs, questions, topics) are adiaphora (not differentiable, not clearly definable, negating Aristotle's use of "diaphora"), astathmēta (unstable, unbalanced, unmeasurable), and anepikrita (unjudgeable, undecidable). Therefore, neither our senses nor our beliefs and theories are able to identify truth or falsehood.
Philologist Christopher Beckwith has demonstrated that Pyrrho's use of adiaphora reflects his effort to translate the Buddhist three marks of existence into Greek, and that adiaphora reflects Pyrrho's understanding of the Buddhist concept of anatta.
The Stoics distinguish all the objects of human pursuit into three classes: good, bad, and adiaphora (indifferent). Virtue, wisdom, justice, temperance, and the like, are denominated good; their opposites were bad. Besides these there are many other objects of pursuit such as wealth, fame, etc. of themselves neither good nor bad. These are thought therefore in ethics to occupy neutral territory, and are denominated "adiaphora". This distinction amounts practically to an exclusion of the adiaphora from the field of morals.
The issue of what constituted adiaphora became a major dispute during the Protestant Reformation. In 1548, two years after the death of Martin Luther, the Holy Roman Emperor Charles V tried to unite Catholics and Protestants in his realm with a law called the Augsburg Interim. This law was rejected by Philipp Melanchthon, because it did not ensure justification by faith as a fundamental doctrine. Later he was persuaded to accept a compromise known as the Leipzig Interim, deciding that doctrinal differences not related to justification by faith were adiaphora or matters not essential for salvation. Melanchthon's compromise was vehemently opposed by Matthias Flacius and his followers in Magdeburg, who went to the opposite extreme by claiming that adiaphora cease to be adiaphora in a case of scandal and confession. By 1576 both extremes were rejected by the majority of Lutherans led by Martin Chemnitz and the formulators of the Formula of Concord.
In 1577, the Formula of Concord was crafted to settle the question of the nature of genuine adiaphora, which it defined as church rites that are "...neither commanded nor forbidden in the Word of God." However, the Concord added believers should not yield even in matters of adiaphora when these are being forced upon them by the "enemies of God's Word".
The Lutheran Augsburg Confession states that the true unity of the Church it is enough to agree concerning the doctrine of the Gospel and the administration of the Sacraments. Nor is it necessary that human traditions, that is, rites or ceremonies, instituted by men, should be everywhere alike.
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The Westminster Confession of Faith, a confession of faith written by the Puritans, which after the English Civil War was rejected by the Anglicans, distinguishes between elements or acts of worship (worship proper) and the circumstances of worship. The elements of worship must be limited to what has positive warrant in Scripture, a doctrine known as the regulative principle of worship. In this framework, the elements of worship have included praise (the words and manner of music), prayer, preaching and teaching from the Bible, the taking of vows, and the two sacraments of baptism and the Lord's Supper, while the circumstances of worship have included the building and its necessary furniture and the time of day for worship.
The circumstances of worship are considered adiaphora, although they must be done for edification and to promote peace and order (compare 1 Cor. 14:26–33; Rom. 14:19). According to the Westminster Confession 20.2, the conscience is left free in general belief and behavior within the realm of whatever is not "contrary to the Word." However, specifically concerning worship and religious faith, the conscience is free from whatever is "besides" Scripture; that is, it is free to worship and believe only according to whatever has positive warrant in Scripture.
Presbyterians who have subscribed to the Westminster Confession, for instance, sometimes considered the questions of musical instruments and of the singing of hymns (as opposed to exclusive psalmody) not drawn directly from the Bible as related to the elements of worship, not optional circumstances, and for this reason they rejected musical instruments and hymns because they believed they were neither commanded by scripture nor deduced by good and necessary consequence from it. Adherence to such a position is rare among modern Presbyterians, however.
The Puritan position on worship is thus in line with the common saying regarding adiaphora: "In necessary things, unity; in doubtful things, liberty; in all things, charity".
Latitudinarianism in Anglicanism
Latitudinarianism was initially a pejorative term applied to a group of 17th-century English theologians who believed in conforming to official Church of England practices but who felt that matters of doctrine, liturgical practice, and ecclesiastical organization were of relatively little importance. Good examples of the latitudinarian philosophy were found among the Cambridge Platonists. The latitudinarian Anglicans of the seventeenth century built on Richard Hooker's position, in Of the Laws of Ecclesiastical Polity, that God cares about the moral state of the individual soul and that such things as church leadership are "things indifferent". However, they took the position far beyond Hooker's own and extended it to doctrinal matters.
- Evangelical counsels
- In necessariis unitas, in dubiis libertas, in omnibus caritas
- Lex orandi, lex credendi
- Modern Stoicism
- "adiaphoron". Oxford Dictionaries. Retrieved 2018-11-16.
- "Adiaphoron". Merriam-Webster.com. Retrieved 2018-11-16.
- Beckwith, Christopher I. (2015). Greek Buddha: Pyrrho's Encounter with Early Buddhism in Central Asia (PDF). Princeton University Press. p. 51. ISBN 9781400866328.
- Beckwith, Christopher I. (2015). Greek Buddha: Pyrrho's Encounter with Early Buddhism in Central Asia (PDF). Princeton University Press. pp. 22–59. ISBN 9781400866328.
- The New American Cyclopaedia, 1859, p. 124.
- Lueker, Erwin L.; Poellot, Luther; Jackson, Paul, eds. (2000). "Adiaphora". Christian Cyclopedia. Concordia Publishing House. Retrieved 2018-05-09.
- "X. Church Rites, Commonly Called Adiaphora". The Solid Declaration of the Formula of Concord. Retrieved 2018-05-09.
- "XX", Westminster Confession of Faith with proofs, Reformed.
- Schwertley, Brian, "Sola Scripture and the Regulative Principles of Worship", Reformed online.
- Schwertley, Brian, "Musical Instruments in the Public Worship of God", Reformed online.
- Schwertley, Brian, "Exclusive Psalmody: A Biblical Defense", Reformed online.
- Waddell, James Alan (2005), The Struggle to Reclaim the Liturgy in the Lutheran Church: Adiaphora in Historical, Theological and Practical Perspective, Lewiston, NY: Mellen, ISBN 0773459227.
- ——— (2009), A Simplified Guide to Worshiping As Lutherans, Eugene, OR: Wipf & Stock.
- The Formula of Concord, CTSFW, archived from the original on 2004-09-04.
- The Augsburg Confession, CTSFW, archived from the original on 2004-08-10.
- Christian Freedom (scholarly articles), The Wisconsin Lutheran Seminary Library[permanent dead link].
- The Lex Orandi Lex Credendi Question in Lutheranism Today
- Chisholm, Hugh, ed. (1911). Encyclopædia Britannica. 1 (11th ed.). Cambridge University Press. p. 192. This specifically describes the Lutheran controversy. .