Eliphaz calls Job out as a sinner, describing the plight of one who is evil, hopeless and stark. He then encourages Job to turn to God, who is the source of all things good, but also the source of judgement to those who do evil. He finishes up by pointing out that God will restore and forgive those who respond to His chastening. He describes in detail the blessings that come to those who turn from their sinfulness.
While the statements of Eliphaz are true in many cases, his rigid interpretation of suffering is narrow and the sense of all negative circumstances being a result of sin is over-reaching. This typical view of sin and punishment from this time was used to explain all suffering, and is flawed. One of the things to note here, is that Job, being the first book written of all the books in the Bible, contains rudimentary theology, not theology typical of later, more well-developed books of the Bible. Progressive revelation is the understanding that as books were written, the theology in each would be able to build on the theology of the previous books. Since Job was early, the theology of a character like Eliphaz was not fully developed, and is corrected by the discourses to be seen later, and the monologue offered by God.