Dale’s now writing a book on the “religious/non-religious mixed marriage”. What I love about his work is that it is positive. Anyway, he writes short daily journal entries while working on his books, the first for his new book points out the problem with our terms. Contrast:
Most people think of someone as religious if they believe in the existence of a God or gods. But many Unitarians, Buddhists, Humanistic Jews and others consider themselves religious even if they do not believe in God.
A slew of surveys show that millions of Americans believe in God but consider themselves nonreligious.
Some more detail in his post, Coming to terms.