《汉书·纪·景帝纪》
景帝元年冬十月，皇上下诏书说： 朕常听闻古代取得天下的祖先有功，治天下的祖宗有德，制礼作乐也就各有由来。
元年冬十月，诏曰： 盖闻古者祖有功而宗有德，制礼乐各有由。
In the eleventh month of the first year of Emperor Jing's reign, the emperor issued an imperial edict, stating: I have heard that the ancestors who obtained the天下 had achievements, and the ancestors who ruled the天下had virtues; therefore, the systems of rites and music all had their origins.