Genesis 12.3
Septuagint

kai euloghsw touV eulogountaV se, kai touV katarwmenouV se katarasomai, kai
eneuloghqhsontai en soi
pasai ai fulai
thV ghV

New Testament - Galatians 3.8

proidousa de h grafh oti ek pistewV dikaioi ta eqnh o qeoV, proeuhggelisato tw Abraam oti 
eneuloghqhsontai en soi 
panta ta eqnh
 

Septuagint

And I will bless those that bless thee, and curse those that curse thee, and in thee shall all the tribes of the earth be blessed

New Testament

And the scripture, foreseeing that God would justify the Gentiles by faith, preached the gospel beforehand unto Abraham, saying, In thee shall all the nations be blessed

Masoretic Text

and I will bless them that bless thee, and him that curseth thee will I curse:  and in thee shall all the families of the earth be blessed

Comments:  The NT, LXX and MT agree - though the NT author has replaced “tribes (or families) of the earth” with an equivalent concept:  “nations.”