I don't know if this will turn into a Godhead debate or not but
Gal 3:18 For if the inheritance comes by the law, it no longer comes by promise;
but God gave it to Abraham by a promise.
Gal 3:19 Why then the law? It was added because of transgressions, until the offspring should come to whom the promise had been made, and it was put in place through angels by an intermediary.
Gal 3:20 Now an intermediary implies more than one, but God is one.
Gal 3:21 Is the law then contrary to the promises of God? Certainly not! For if a law had been given that could give life, then righteousness would indeed be by the law.
Heb 6:13 For when God made promise to Abraham, because He could swear by no greater, He swore by Himself,