Naturalists, like atheists, do not believe in an actual God that can cause miracles.
But rather than the focus in the word, atheist, on what is not believed, those who describe themselves as naturalists choose to focus on what is believed in a worldview based in an understanding of the natural world. One thought in preferring this name is that naturalist gives a more positive focus and a broader scope that can include appreciation for some approaches to religion.
Those who don’t believe in God have a range of views about religion.
Some are actively opposed.
Some don’t think about it much.
Some acknowledge a spiritual sense, but understand this in non-traditional ways.
A number of terms may be used to describe these views, including “atheist”, “secular”, “skeptic”, “agnostic”, “freethinker”, and “Humanist”. Some people describe themselves as “spiritual but not religious”. Some say they have “no religion”. And, when shades of meaning are considered, “spiritual atheist”, “religious naturalist”, and other multiple-word terms may be used.
Sometimes care is taken in choice of words that are used to describe religious views. But often a term is used casually as the first that comes to mind, with limited thought about meaning and options.
It can be worth thinking about terms that fit one’s views on spirit and religion. A related question is when to use different terms, based on how they may be received by listeners.
With disbelief in traditional images of an active personal God, all naturalists are atheists. But, with a desire to not define one’s views in relation to traditional belief, many atheists and seculars choose to describe themselves as naturalists.