What are the promises?
What does it mean to be a blessing?
The Hebrew root, ברך (brk), “bless,” is widely understood as referring to “health-creating power”; someone who is בְּרוּךְ (berukh), “blessed,” is gifted with such power, while to bless someone is either to bestow such power on them (often by means of a verbal statement) or to declare that they have such power
The Priestly author of Genesis 1 places the divine blessing on humankind at the beginning of his work (1:28); but the Yahwist chapters that follow are a narrative dominated by God’s curse, from the man and woman (Gen. 3:16-19) to Cain (4:11) to the Flood and the renewal of the divine blessing to its survivors (9:1). The cycle of sin and curse begins again, climaxing in the hybris of the Tower of Babel (11:1-9), but it is countered now by a new act of God, the blessing of Abram (12:1-3). This is the beginning of a history of blessing (22:15-18; 24:60; 26:2-4) that culminates in the blessing of Jacob by Isaac (27:27-29) and by God (32:27).
So … Why Abraham? … Why not?
I will bless those who bless you, and the one who curses you I will curse;
by you all the families of the earth shall bless themselves