something that is difficult or impossible to understand or explain.
the mysteries of outer space
a novel, play, or movie dealing with a puzzling crime, especially a murder.
Thrillers, mysteries and crime novels are perennial favorites for summertime reading.
the secret rites of Greek and Roman pagan religion, or of any ancient or tribal religion, to which only initiates are admitted.
His Protrepticus is a copious source of information about the Greek mysteries , though his wish to represent them as a perversion of Scriptural teachings must have led to misrepresentation.
a religious belief based on divine revelation, especially one regarded as beyond human understanding.
the mystery of Christ