Gregory the Great

(Mor. 16, 55) The different ranks in which those who ate lie down, mark out the divers churches which make up the one Catholicx. But the Jubilee rest is contained in the mystery of the number fifty, and fifty must be doubled before it reaches up to a hundred. As then the first step is to rest from doing evil, that afterwards the soul may rest more fully from evil thoughts, some lie down in parties of fifty, others of a hundred.