TYB
BOXING DAY believed to be in reference to the alms box placed in the narthex of Christian churches to collect donations for the poor. Boxes placed in churches were used to collect special offerings tied to the Feast of Saint Stephen, which, in the Western Christian Churches, falls on the same day as Boxing Day, the second day of Christmastide.On this day, it is customary in some localities for the alms boxes to be opened and distributed to the poor.
The Oxford English Dictionary gives the earliest attestations from Britain in the 1830s, defining it as "the first weekday after Christmas day, observed as a holiday on which postmen, errand boys, and servants of various kinds expect to receive a Christmas box".
The term "Christmas box" dates back to the 17th century, and among other things meant:
A present or gratuity given at Christmas: in Great Britain, usually confined to gratuities given to those who are supposed to have a vague claim upon the donor for services rendered to him as one of the general public by whom they are employed and paid, or as a customer of their legal employer; the undefined theory being that as they have done offices for this person, for which he has not directly paid them, some direct acknowledgement is becoming at Christmas.
https://en.wikipedia.org/wiki/Boxing_Day
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