《禮記．祭統五》

5	祭統:	是故，天子親耕於南郊，以共齊盛；王后蠶於北郊，以共純服。諸侯耕於東郊，亦以共齊盛；夫人蠶於北郊，以共冕服。天子諸侯非莫耕也，王后夫人非莫蠶也，身致其誠信，誠信之謂盡，盡之謂敬，敬盡然後可以事神明，此祭之道也。
	Ji Tong:	For this reason, also, the son of Heaven himself guided the plough in the southern suburb, to provide the grain for the sacrificial vessels; and the queen looked after her silkworms in the northern suburb, to provide the cap and robes of silk. The princes of the states guided the plough in their eastern suburb, also to provide the grain for the sacrificial vessels, and their wives looked after their silkworms in the northern suburb, to provide the cap and robes of silk. This was not because the son of Heaven and the princes had not men to plough for them, or ‘because the queen and the princes’ wives had not women to tend the silkworms for them; it was to give the exhibition of their personal sincerity. Such sincerity was what is called doing their utmost; and such doing of their utmost was what is called reverence. When they had reverently done their utmost, they could serve the spiritual Intelligences–such was the way of sacrificing.