devout person; person of faith
Refers to someone who is deeply religious or pious, often with a connotation of sincerity and earnestness in their beliefs.
She is a devout person and goes to the temple every morning to pray.
My grandfather, a man of faith, never missed a prayer of gratitude no matter the circumstances.
宗教家 refers to a religious leader or expert, whereas 信心家 describes a layperson known for their deep faith.
Compound of 信心 (faith, belief) and 家 (person with a certain trait or occupation).