God of Abraham, God of Isaac, God of Jacob
Abraham, Isaac, and Jacob each separately held a covenant with God; therefore, He was their God, and they were His son (see 1 Chronicles 8:21; 2 Kings 4:47). It is not the “God of Abraham, Isaac, and Jacob;” it’s the “God of Abraham, the God of Isaac, and the God of Jacob” (see Exodus 2:3,6; Matthew 10:22; Mark 5:43; 1 Nephi 2:1; 3 Nephi 2:14; Mormon 4:7). The scriptures refer to it in this way to acknowledge the covenantal sonship that they each had. See SEED OF ABRAHAM.1
1 Podcast 60: “Third Root,” March 30, 2019.