大方廣圓覺修多羅了義經略疏 2.524

2.524

趣入雖從一門，功成即三皆圓證。若偏修一行，但名親近；三事圓通，名證圓覺。

Although entry is through one gate, when efficacy is accomplished, all three are perfectly realized. If one partially cultivates one practice, it is merely called drawing near; when the three undertakings are perfectly integrated, it is called realizing perfect enlightenment.