I've only heard of people sleeping on the bed or on the floor, but I've never heard that you can sleep on the wall. But there was one person who could, and that was Ma Xiang, a Taoist priest in the Tang Dynasty.

    Ma Xiang, the word nature, is Hangzhou Yanguan (present-day Haiyan County, Zhejiang Province) people. When he was young, he visited Taoist monasteries all over the world, and after he finished his studies, he was very capable. He was very skillful in changing games. For example, before the banquet, in a ceramic pot to hold some soil planted melon seeds, a moment melon seedlings will break out of the ground, stretching out branches and vines. Blossoms and fruits, the melon to eat it, tasted people in unison, are said to be more fragrant than the usual melon. Another example is the city of Changzhou in Jiangsu Province, which was full of rats, and Ma Zhi, the governor of the city, asked Ma Xiang to think of a way to cure it. Ma Xiang drew a talisman and told him to stick it on the south wall. When he struck the plate with chopsticks and whistled under his breath, rats came out in droves and crouched under the talisman. Ma Xiang called out to the rats to come over, a big rat answered and came to the front of the steps, Ma Xiang said to it: "You little things, God has given you food, how dare you make holes in people's houses and harass the assassin day and night? For the time being, I will be merciful and not kill you all. You should lead your group of rats to leave this place." The rat returned to the group, led the group of rats to kowtow and thanked him, and then countless rats ran out of the city gate in groups. The rats became extinct in Changzhou.

    Once again, Ma Xiang and Taoist priests Wang Zhiwei and Wang Yanxuo traveled around, and came to an inn in the evening, where there were few rooms and many travelers had arrived. The owner of the inn joked, "My store is full, if the Taoist priest can sleep on the wall, then you will be allowed to stay." By this time, it was already dark, and Wang Zhiwei and his wife were eager to stay in the store to rest, so Ma Xiang said to them, "For the time being, you should sleep with the common people, and I will sit here until dawn." After everyone had fallen asleep, Ma Xiang jumped up to the roof beam, hooked one foot on the beam, and hung upside down to sleep. When the owner of the store got up at night, he was amazed to see this sleeping face in the candlelight, and Ma Xiang said, "If I can sleep on the beam, what's so difficult about the wall? He said he went into the wall to sleep, and didn't come out for a long time. The owner of the store knew that he had met a strange man, and hurriedly invited Ma Xiang to come out, and invited Wang Zhiwei and Wang Yanshou to a clean room in the inner mansion to settle down, and only then did Ma Xiang come down from the wall. Only then did Ma Xiang come down from the wall. After daybreak, the shopkeeper was busy entertaining Ma Xiang, but he had already disappeared. Zhiwei and Yanxu traveled a few miles before they saw Ma Xiang waiting for them by the roadside.

    只听说人睡在床上、地上，没有听说可以睡在墙上的。可有一个人就会，那就是唐朝的道士马湘。

    马湘，字自然，是杭州盐官(今浙江海盐县)人。年轻时就到处访道，学成后很有些能耐。变化游戏的法儿是件都精。比如酒席之前，在瓷盆中盛点土种上瓜籽，一会儿瓜秧便破土而出，伸出枝蔓。开花结果，把瓜拿来一吃呢，尝过的人异口同声，都说比寻常的瓜更加香美。又比如江苏常州城中到处是老鼠，刺史马植请马湘想法子治一治。马湘就画一张符，让他贴在南边墙壁上，自己用筷子击着盘，口中长啸，老鼠便成群结队地跑出来，匍伏在符下。马湘呼喝老鼠过来，有只大鼠应声走到台阶前，马湘对它说：“你们这些小东西，老天爷已赐给了你们食物，怎么还敢在人房屋中打洞，没日 没夜地骚扰刺史?我暂且以慈悲为怀，不把你们杀绝，你赶快率领群鼠离开此地。”大鼠回到鼠群前，率领群鼠叩头谢过，然后无数老鼠成群地跑出城门去。常州城里一时老鼠绝迹。

    又一次，马湘和道士王知微、王延叟云游各处，这天傍晚来到家旅店投宿，房少，旅客到的已不少。店主人开玩笑说：“敝店已住满，道士如果能睡在墙壁上，那便容你们住宿。”这时天已黑下来，王知微二人急于住店休息，马湘对他们说：“你们暂且和俗各们混在一起睡罢，我在这儿坐到天亮。”众人都睡着之后，马湘跃身上了屋梁，用一只脚勾在梁上，倒挂着睡。店主人晚上起来，烛光中见到这副睡相十分惊异，马湘说：“梁上都能睡，墙上又有什么难处。”说道便进入墙壁去睡，很久都不出来。店主人知道遇上了奇人，急忙恭请马湘出来，又将王知微、王延叟请到内宅干净房间安顿，马湘这才从墙上下来。天亮后，店主人忙着来招待马湘，却早已不见他的身影。知微、延叟走了几里路，才见马湘正在路边等着他们呢。