Asceticism: Sleeping on the Floor or with Hard Bedding

Some saints seem to have had this practice:

ST. COLUMBA, the apostle of the Picts, was born of a noble family, at Gartan, in the county of Tyrconnel, Ireland, in 521. From early childhood he gave himself to God. In all his labors--and they were many--his chief thought was heaven and how he should secure the way thither. The result was that he lay on the bare floor, with a stone for his pillow, and fasted all the year round; yet the sweetness of his countenance told of the holy soul's interior serenity. Though austere, he was not morose; and, often as he longed to die, he was untiring in good works, throughout his life.

[St.] Lupicinus used no other bed than a chair or a hard board; never touched wine, and would scarcely ever suffer a drop either of oil or milk to be poured on his pottage. In summer his subsistence for many years was only hard bread moistened in cold water, so that he could eat it with a spoon. His tunic was made of various skins of beasts sewn together,. with a cowl; he used wooden shoes, and wore no stockings unless when he was obliged to go out of the monastery.

ST. FRANCIS OF PAULA. AT the age of fifteen Francis left his poor home at Paula in Calabria, to live as a hermit in a cave by the seacoast. In time disciples gathered round him, and with them, in 1436, he founded the "Minims," so called to show that they were the least of monastic Orders. They observed a perpetual Lent, and never touched meat, fish, eggs, or milk. Francis himself made the rock his bed; his best garment was a hair-shirt, and boiled herbs his only fare. As his body withered his faith grew powerful, and he "did all things in Him Who strengthened him." He cured the sick, raised the dead, averted plagues, expelled evil spirits, and brought sinners to penance. A famous preacher, instigated by a few misguided monks, set to work to preach against St. Francis and his miracles. The Saint took no notice of it, and the preacher, finding that he made no way with his hearers, determined to see this poor hermit and confound him in person. The Saint received him kindly, gave him a seat by the fire, and listened to a long exposition of his own frauds. He then quietly took some glowing embers from the fire, and closing his hands upon them unhurt, said, "Come, Father Anthony, warm yourself, for you are shivering for want of a little charity" Father Anthony, falling at the Saint's feet, asked for pardon, and then, having received his embrace, quitted him, to become his panegyrist and attain himself to great perfection.

via Lives of the Saints, by Alban Butler, Benziger Bros.