Moses
Genesis 12:2ESV·traditional attribution

And I will make of you a great nation, and I will bless you and make your name great, so that you will be a blessing.

John Calvin Reformed @genevareformer

2. And I will make of thee a great nation . Hitherto Moses has related what Abram had been commanded to do; now he annexes the promise of God to the command; and that for no light cause. For as we are slothful to obey, the Lord would command in vain, unless we are animated by a superadded confidence in his grace and benediction.

Matthew Henry Presbyterian @wholebiblehenry

We have here the call by which Abram was removed out of the land of his nativity into the land of promise, which was designed both to try his faith and obedience and also to separate him and set him apart for God, and for special services and favours which were further designed.

Commenting on Genesis 12:1-3

John Gill Reformed Baptist @doctorgill

And I will make of thee a great nation,.... In a literal sense, as the people of the Jews were that descended from him, and in a spiritual sense believers in all ages and of all nations, that walk in the steps of the faith of Abram, who are his children, and are blessed with him: and I will bless thee; not only with temporal...