《汉书·传·匡张孔马传》
皇上认为可以担任公卿的职责了，因此任命匡衡为光禄勋、御史大夫。
上以为任公卿，由是为光禄勋、御史大夫。
The Emperor felt he could bear the responsibility of a high official, thus appointing Kuang Heng as the Grand Usher and Master of Imperial Censors.