The word religion carries a number of meanings, including:
[Fundamentally] a manner of living in accord with a belief in the existence of a soul and a god, and in life after death (conditional or unconditional), with the associated beliefs in divinely given moral and other commandments whose transgressions bring punishment in the hereafter. Usually, but not inevitably, religion entails public worship and other external manifestations (fasts, feasts, mutual help among believers, distinctive greetings, clothes or manners, a holy book, holy places, etc.).
[Intellectually] the attempt to account for man and the universe before the development of scientific method. Insecurity was the key drive in the creation of religion and the chief metaphor of a father god in heaven was based on the model of one or several of the principle bodies of the solar system, i.e. Saturn, Jupiter and the Sun, or on singular comets which approached the Earth. Modern religious forms include those which have no pronounced influence on behaviour and require mainly intellectual assent to a number of abstract propositions such as belief in an absolute being or substance (mind or matter), the fellowship of man, the goodness of the world, the sufficiency of ethics or ethical philosophy to guide human affairs, human progress, evolution, the all-conquering nature of human reason, and similar ideas.
[Ideology] including anti-religion.