"Because the use of eggs was forbidden during Lent, they were brought to the table on Easter Day, coloured red to symbolize the Easter joy. This custom is found not only in the Latin but also in the Oriental Churches. Coloured eggs are used by children at Easter in a sort of game which consists in testing the strength of the shells (Kraus,"
January 1, 1970
https://en.wikiquote.org/wiki/Easter