I took this picture a few days ago along the Ganges in Varanasi (Benaras).
Water is of course very important here, it is a purifier like in most other religions.
Major faiths that incorporate ritual washing (ablution) include Christianity, Hinduism, Rastafarianism, Islam, Shinto, Taoism, and Judaism.
Immersion (or aspersion or affusion) of a person in water is a central sacrament of Christianity (where it is called baptism); it is also a part of the practice of other religions, including Judaism (mikvah) and Sikhism (Amrit Sanskar).
In addition, a ritual bath in pure water is performed for the dead in many religions including Judaism and Islam.
In Islam, the five daily prayers can be done in most cases after completing washing certain parts of the body using clean water (wudu).
In Shinto, water is used in almost all rituals to cleanse a person or an area.
Some faiths use water especially prepared for religious purposes (holy water in some Christian denominations, Amrita in Sikhism and Hinduism).
Many religions also consider particular sources or bodies of water to be sacred or at least auspicious; examples include Lourdes in Roman Catholicism, the Jordan River (at least symbolically) in some Christian churches, the Zamzam Well in Islam and the River Ganges (among many others) in Hinduism.
Water is often believed to have spiritual powers.
In Celtic mythology, Sulis is the local goddess of thermal springs; in Hinduism, the Ganges is also personified as a goddess, while Saraswati have been referred to as goddess in Vedas.
Also water is one of the "panch-tatva"s (basic 5 elements, others including fire, earth, space, air).
In Islam, not only does water give life, but every life is itself made of water: "We made from water every living thing" ( Sura of Al-Anbiya).
Water was also one of the five elements in traditional Chinese philosophy, along with earth, fire, wood, and metal.