《新唐书·列传·卷一百四十七》
法下马与来客相见，问候天子安好，取过使者的佩刀观看，自己解下左右的慈双羽给使者看。
问天子起居，下马揖客，取使者佩刀视之，自解左右钮以示。
Fa dismounted and greeted the guest, asking about the emperor's well-being, and then took the messenger's saber to look at it, and took off his own feather sword on his left and right to show the messenger.