When betrothing a woman, the groom says "Behold, you are betrothed to me with this ring, according to the tradition of Moshe and Israel."
As explained in that article, "according to the tradition of Moshe and Israel" means according to the Torah. (See Tosfot Ketubot 3A dh Adata.)
I assume that "Moshe" refers to Biblical Law, and "Israel" refers to Rabbinical Law, so why not say so explicitly? What is the significance of 'Moshe' and 'Israel'?