church-goer
Regular pew occupant
A church-goer is someone who regularly attends church services.
The term is neutral and descriptive, simply indicating the habit of attendance rather than suggesting any particular level of devotion or belief.
She wasn't raised religious but became a regular church-goer after moving to the small town.
The hyphenated spelling is common, though churchgoer as one word appears with equal frequency.
piety
Sincere religious devotion
fervent · faithful · believer · observant · practicing · devoted · sincere · committed · steadfast · spiritual
parishioner
Member of a congregation
pastor · minister · rector · deacon · choir · altar · nave · chapel · vestry · sacristy
church-goerbackslider
One who reverts
unchurched · non-practicing · stay-at-home · apostate · fallen away
church-goeratheist
One denying gods exist
nonbeliever · unbeliever · agnostic · secularist · infidel