The idea that Shakyamuni was not the only Buddha to appear in history, but that Buddhas had appeared in the past and will appear in the future, existed before Mahayana; however, according to Mahayana Buddhism, countless Bosatsu had completed the path to becoming a Buddha by attaining enlightenment, and each of them exists in their own world, separate from this corrupt world both temporally and spatially.
ブッダとは歴史上にあらわれた釈迦だけに限らず、過去にもあらわれたことがあるし未来にもあらわれるだろうとの考えはすでに大乗以前から出てきていたが、大乗仏教ではこれまでに無数の菩薩たちが成道し、娑婆世界とは時空間を別にしたそれぞれの世界でそれぞれのブッダとして存在していると考えた。