At this point, Abinadi begins to reprise Isaiah, with an interpretation such as a modern Christian might apply. This comes because of his foreknowledge of the details of Jesus mission through Nephite revelation. Rather than the hindsight of the Chirstian commentator, Abinadi speaks with the foreknowledge of prophets to whom the details were revealed (Nephi certainly has these details, see 1 Nephi 11). Here he reprises the suffering images from Isaiah and directly relates them to the Son of God - the "God himself" that Abinadi is preaching. The scourging and casting out also reprise Isaiah (see Isaiah 53: 4-5).
Abinadi's addition to Isaiah is that the atoning Messiah will not yield to temptation. This conception of the innocent Messiah may also be behind the translation we saw for Isaiah 53: 9 where the Book of Mormon stresses that the servant has done no evil, where the KJV has no "violence" (see the commentary on that verse).