《北史·列传·卷四十五》
当初，杨坚还没有当皇帝时曾对宇文庆说 ：天元皇帝品质平平，没有积德，从他的相貌看，寿命也不会太长。加上他制定的法令严厉繁苛，他又天天沉湎于声色之中，让我看他不会长久。
初，文帝龙潜时，尝与庆言，谓曰： 天元质无积德，其相貌寿亦不长，加以法令繁苛，耽恣声色，以吾观之，殆将不久。
Before, Yang Jian, when he had not yet become emperor, used to say to Yuwen Qing: Emperor Tianyuan is very mediocre, and has gathered no merit; judging from his appearance, his life will not be very long. Add to that, he enacts very harsh and unreasonable laws, and every day he indulges in sensual pleasures; it will not be long before he destroys himself.