An amusing theory Stephen but according to Catholic literature:Altar rail. Introduced by Archbishop Laud of questionable memory in the 17th century to keep the dogs away. Edit to add: Seriously!
An amusing theory Stephen but according to Catholic literature:
"The Communion rail (sometimes called the altar rail) was introduced into Catholic churches in the ninth century. Its purpose was to set off the sanctuary from the rest of the church and to separate those whose duty it is to perform the sacramental action from those who form the celebrating congregation – a separation which was always taken for granted as essential to the Church’s constitution. This was in keeping with the ancient understanding of priest as the appointed intermediary between God and the people. The altar railing became better known as the Communion rail in the Middle Ages, when the faithful more widely began to receive Communion kneeling. This organic developed grew out of a pressing sense of reverence and humility toward the Eucharist."
... which is probably more in keeping methinks.