Malachi 1:1–5: Why the Book Begins With God's Love
Malachi begins by answering a wounded question, how have you loved us, with God's free choice of Jacob over Esau. That settled love is the ground for everything the book goes on to demand.
Why God Chose Israel: Deuteronomy 7:6–8
Deuteronomy 7:6–8 grounds God's choice of Israel entirely in his own love and his sworn promise to the fathers. The text rules out the obvious human explanation: Israel was the fewest of peoples, not the greatest.