信仰

religious creed/belief

political creed/conviction

national faith

communist belief; belief in communism

belief in socialism

freedom of belief

respect sb's faith

lose one's faith

affirm one's faith

adhere to/keep one's belief

defend one's faith

alter one's belief

renounce/forsake one's faith; recant/abjure one's faith

break faith

He is Buddhist by faith./ He professed a belief in Buddhism.

have faith in God