Isaiah 8.14
Septuagint

kan ep autw pepoiqwV hV, estai soi eiV agiasma, kai ouc wV liqou proskommati sunanthsesqe, oude wV petraV ptwmati:  oi de oikoi Iakwb en pagidi, kai en koilismati egkaqhmenoi en Ierousalhm
 

New Testament - Romans 9.33

idou tiqhmi en Ziwn
liqon proskommatoV kai petran skandalou

1 Peter 2.8

liqoV proskommatoV kai petra skandalou

Septuagint

And if thou shalt trust in him, he shall be to thee for a sanctuary; and ye shall not come against him as against a stumbling-stone, neither as against the falling of a rock:  but the houses of Jacob are in a snare, and the dwellers in Jerusalem in a pit

New Testament

Romans 9.33:  Behold, I lay in Zion a stone of stumbling and a rock of offence

1 Peter 2.8:  A stone of stumbling, and a rock of offence

Masoretic Text

And he shall be for a sanctuary; but for a stone of stumbling and for a rock of offence to both the houses of Israel, and for a gin and for a snare to the inhabitants of Jerusalem

Comments:  The NT and the MT agree.  The LXX does not mention the rock “of offence.”  The initial and final words from Romans 9.33 are provided by Isaiah 28.16.