Genesis 22.16-17
Septuagint

legwn, kat  emautou wmosa, legei kurioV, ou eineken epoihsaV to rhma touto, kai ouk efeisw tou uiou sou tou agaphtou di eme, 
h mhn eulogwn euloghsw se, kai plhqunwn plhqunw to sperma sou, wV touV asteraV tou ouranou, kai wV thn ammon thn para to ceiloV thV qalasshV:  kai klhronomhsei to sperma sou taV poleih twn upenantiwn

New Testament - Hebrews 6.13-14

tw gar Abraam epaggeilamenoV o qeoV, epei kat oudenoV eicen meizonoV omosai, wmosen kaq eautou legwn: 

ei mhn eulogwn euloghsw se kai plhqunwn plhqunw se

 

Septuagint

saying, I have sworn by myself, says the Lord, because thou hast done this thing, and on my account hast not spared thy beloved son, surely blessing I will bless thee, and multiplying I will multiply thy seed as the stars of heaven, and as the sand which is by the shore of the sea, and thy seed shall inherit the cities of their enemies. 

New Testament

For when God made promise to Abraham, since he could swear by none greater, he sware by himself, saying, Surely blessing I will bless thee, and multiplying I will multiply thee

 

Masoretic Text

and said, By myself have I sworn, saith Jehovah, because thou hast done this thing, and hast not withheld thy son, thine only son, that in blessing I will bless thee, and in multiplying I will multiply thee as the stars of the heavens, and as the sand which is upon the seashore; and thy seed shall possess the gate of his enemies; 

Comments:  The NT, LXX and MT agree.