In the opening sentences of The Sociology of Religion Max Weber (1922) states, "To define 'religion,' to say what it is, is not possible at the start of a presentation such as this. Definition can be attempted, if at all, only at the conclusion of the study".
He could offer only the broadest of definitions: religion encompasses those human responses that give meaning to the ultimate and inescapable problems of existence—birth, death, illness, aging, injustice, tragedy, and suffering.
To Weber, the hundreds of thousands of religions, past and present, represented a rich and seemingly endless variety of responses to these problems. In view of this variety, he believed that no single definition could hope to capture the essence of religion.
Like wise Emile Durkheim believed that religion is difficult to define. In the first chapter of his book The Elementary Forms of the Religious Life, Durkheim cautions that when studying religions, sociologists must assume that "there are no religions which are false".
In sacramental religions, followers seek the sacred in places, objects, and actions believed to house a god or a spirit. These locations may include inanimate objects such as relics, statues, and crosses, animals, trees or other plants, foods, drink such as wine and water, places, and certain processes such as the way people prepare for a hunt or perform a dance. Sacramental religions include various forms of Native American spirituality.
In prophetic religions, the sacred revolves around items that symbolize historic events or around the lives, teachings, and writings of great people. Sacred books, such as the Christian Bible, the Muslim Qur'an, and the Jewish Tanakh, hold the records of these events and revelations. In the case of historic events, God or some other higher being is believed to be directly involved in the course and outcome of the events (such as a flood, the parting of the Sea of Reeds, or the rise and fall of an empire).
In mystical religions, followers seek the sacred in states of being that can exclude all awareness of their existence, sensations, thoughts, and surroundings. In such states, mystics become caught up so fully in the transcendental experience that earthly concerns seem to vanish. Direct union with the divine forces of the universe assumes the utmost importance.