How (Not) to Celebrate the New Year: Advice from 700 AD (or thereabouts)

Ask The Past (via their blog): "If anyone does what many do on the first day of January, that is to say, goes around in the costume of a stag or a calf (which still remains from pagan custom), he must do penance for three years, because this is demoniacal." 

~Burgundian Penitential (c. 700)