Dies lustricus, a rite of passage

The dies lustricus (purification day), for the ancient Romans, was the day when the newborn child was officially welcomed into the family, after having been purified in the rite of lustratio through various instruments that may have been water (aqua lustralisi), olive branches or some plant species.
The rite of lustratio would involve various areas of life in Rome; those practised in families were propitiatory rites to ensure the newborn child’s protection by a deity.