Q:

What is a good word for 'being a group where different beliefs are practiced'? 

What is a good word for being a group where different beliefs are practiced? 
I.e. wearing a headscarf, being a atheist or doing a silent prayer for diner are common. 
Secular means an organisation is not religious by itself but implies we expect people to be secular.  And pluriform could also cover cultural properties but hasn't that much to do with religions.  

A:

You could say your group is diverse:

showing a great deal of variety; very different. 
"a culturally diverse population"
synonyms:  various, sundry, manifold, multiple; varied, varying, miscellaneous, assorted, mixed, diversified, divergent, heterogeneous, a mixed bag of; different, differing, distinct, unlike, dissimilar; literarydivers, myriad

Or eclectic:

deriving ideas, style, or taste from a broad and diverse range of sources. 
a person who derives ideas, style, or taste from a broad and diverse range of sources.