釋氏要覽 2.117

2.117

律難陀比丘。嚴飾床褥為人譏云。此太嚴麗。非比丘所宜。佛制不得過量嚴飾床褥。

The Vinaya says: 'The monk Nanda elaborately adorned his bed and mattress, and was ridiculed by people, saying: "This is too ornate and beautiful, not suitable for a monk." The Buddha established the rule that one must not excessively adorn beds and mattresses.'