auricular confession:

(aka Sacrament of Penance) method which individuals confess sins committed after baptism & receive absolution from the Priest. Usually conducted within a confessional box and is private; intent of this sacrament is to provide healing for the soul as well as to regain the grace of God, lost by sin.  It can be traced back to the 11th century.  In 1215, the Fourth Lateran council required every Christian, having reached the age of discretion, to confess their sins at least once a year to their own priest.

 

acuity:

sharpness; acuteness; keenness