《容斋随笔·卷七·姜嫄简狄》
《玄鸟》中，有 天命玄鸟，降而生商 一句，毛公作注说： 春分时燕子飞来，简狄配高辛氏帝喾，帝喾和简狄为求子而在郊外向上帝祈祷，因而生下了商的祖先契，所以契是受命于天，在燕子到来时才出生的。 
《玄鸟》诗， 天命玄鸟，降而生商 之句，曰： 春分玄鸟降，简狄配高辛帝，帝与之祈于郊祺而生契，故本其为天所命，以玄鸟至而生焉。 
In "Xuanniao", there is the line, "Ordered by Heaven, the blackbird came and Shang was born." Mao's annotations say, "At the spring equinox, a swallow flew in and Jian Di mated with Emperor Ku of Gaoxin. Hoping to conceive a child, the emperor and Jian Di prayed to Heaven in the countryside and so was born Qi, the ancestor of Shang. Qi's birth was thus ordered by Heaven and occurred when swallows came."