What does "penitential" mean?

Penitential: Of or pertaining to penitence, or to penance; expressing penitence; of the nature of penance; as, the penitential book; penitential tears. "Penitential stripes." Cowper. Guilt that all the penitential fires of hereafter can not cleanse. Sir W. Scott.

Additional senses

  1. 2.A book formerly used by priests hearing confessions, containing rules for the imposition of penances; -- called also penitential book.

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