Oyamatsumi said, 'The reason why I offered my two daughters together was that I made a vow that by making Iwanagahime your wife, the son of Amatsukami (Ninigi)'s life would be as eternal as a rock, and by making Konohana sakuyabime your wife, you would prosper as a tree flowers. Because you married only Konohana sakuyabime, the son of Amatsukami's life will be short just as flowers on a tree' (the "Kojiki").
オオヤマツミは「私が娘二人を一緒に差し上げたのは、イワナガヒメを妻にすれば天津神の御子（ニニギ）の命は岩のように永遠のものとなり、コノハナノサクヤビメを妻にすれば木の花が咲くように繁栄するだろうとうけい（うけひ）をしたからである。コノハナノサクヤビメだけと結婚したので、天津神の御子の命は木の花のようにはかなくなるだろう」（「我之女二並立奉者有因使石長姬者天神御子之命雖雪零風吹恆可如石而常堅不動坐亦使木花之佐久夜姬者如木花之榮榮坐因立此誓者而使二女貢進今汝令返石長姬而獨留木花之佐久夜姬故今後天神御子之御壽者將如木花之稍縱即逝矣」『古事記』）と言った。