What word in English is used to describe a person who doesn't believe in religion but believes in the existence of God?

You could call them a Quaker. There's no minister, no preacher, no organized service in that religion, though they believe in God.

Theist, Deist, and most Spiritualists.

There are a couple of words: Deist, Theist http://www.merriamwebster.com/dictionary/deist http://www.merriamwebster.com/dictionary/Theist These are off of the top of my head.

theist

Spiritual!

A deist- Deism (ˈdi:iz(ə)m)[1] or (ˈdē-ˌi-zəm)[2] is a religious and philosophical belief that a supreme being created the universe, and that this (and religious truth in general) can be determined using reason and observation of the natural world alone, without a need for either faith or organized religion. Deists tend to, but do not necessarily, reject the notion of divine interventions in human affairs, such as by miracles and revelations. These views contrast with a dependence on revelations, miracles, and faith found in many Judeo-Christian, Islamic and other theistic teachings.

there is no such thing as a christian God as i believe jews and muslims believe in the same God..so does that mean he has three names, 'The Christian God, The Jewish God and The Muslim God'? No..rather the Lord is truly The one and ONLY God.

I believe Agnostic is defined as someone who believes there is a God, but does not worship Him or follow His word. My own opinion, of course. God Bless, <:))))<><

Confused