Seiji yoryaku (examples of the politics in the Heian period), there is a description that 'saniwa is a person who plays koto and dedicates its music to the god.'
平安時代の『政事要略』に「今琴弾之者を以て佐爾波（さにわ）と云、偏に以て神遊に供奉す」とある。