In the Greek Chasoslov (Orologion) of 1897 is explained thus the derivation of this feast: "By reason of the sicknesses, often everywhere occurring in August, from of old customarily it was done at Constantinople to carry out the Venerable Wood of the Cross along the roads and streets for the sanctifying of places and for the driving away of sicknesses. On the eve (31 July), carrying it out from the imperial treasury, they placed it upon the holy table of the Great Church (in honour of Saint Sophia – the Wisdom of God). From this feastday up to the Dormition of the Most Holy Mother of God, making litia throughout all the city, they then placed it forth for all the people to venerate. This also is the Issuing-forth of the Venerable Cross".
In the Russian Church this feast is combined also with a remembrance of the Baptism of Rus', on 1 August 988. In the "Account about the making of services in the holy catholic and apostolic great church of the Uspenie-Dormition", compiled in 1627 by order of the Patriarch of Moscow and All Rus' Philaret, there is provided suchlike an explanation of the feast: "And on the day of the procession of the Venerable Cross there occurs a church-procession for the sanctification of water and for the enlightenment of the people, throughout all the towns and places".
Knowledge of the day of the actual Baptism of Rus' was preserved in the Chronicles of the XVI Century: "The Baptism of Great-prince Vladimir of Kiev and all Rus' was on August 1".
In the practice now of the Russian Church, the service of the Lesser Sanctification of Water on 1 August is done either before or after Liturgy. Together with the Blessing of Waters, there is made a Blessing of Honey (i.e. first-honey for the Saviour: "Saviour of the Water", "Saviour Moisture" [apparently in place of the vinegar and gall offered Him on the Cross?]). And from this day the newly harvested honey is blessed and tasted.