The custom of chalking the doors yearly just after Christmas was explained to me as commemorative of the visitation by the 3 wise men who sought him assiduously were guided by the heavenly light to his place at the manger -- that we who dwell in places with doors should remember that such places were denied to Mary when she and Joseph sought accommodations at an inn -- that we would do wisely to ask the Lord's blessings upon our doors -- which were symbolic of the shelter to which they regulated access -- the blessing was addressed directly to the door -- approximately "mayfrom Psalm 121.8: May the Lord bless all your goings-inkeep thy going in and your comings-outthy going out; from henceforth now and forever"for ever.