Gregory the Great
Catena Aurea · Matthäusevangelium 18
At the same time came the disciples unto Jesus, saying, Who is the greatest in the kingdom of heaven? And Jesus called a little child unto him, and set him in the midst of them, And said, Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven. Whosoever therefore shall humble himself as this little child, the same is greatest in the kingdom of heaven. And whoso shall receive one such little child in my name receiveth me. But whoso shall offend one of these little ones which believe in me, it were better for him that a millstone were hanged about his neck, and that he were drowned in the depth of the sea.
(Mor. vi. 37.) Otherwise; What is denoted by the sea, but the world, and what by the mill-stone, but earthly action? which, when it binds the neck in the yoke of vain desires, sends it to a dull round of toil. There arc some who leave earthly action, and bond themselves to aims of contemplation beyond the reach of intellect, laying aside humility, and so not only throw themselves into error, but also cast many weak ones out of the bosom of truth. Whoso then offends one of the least of mine, it were better for him that a mill-stone be tied about his neck, and he be cast into the sea; that is, it were better for a perverted heart to be entirely occupied with worldly business, than to be at leisure for contemplative studies to the hurt of many.