Why do passages about Israel and passages about the church seem contradictory?
They seem contradictory because one passage may describe God's dealing with Israel, while another describes His dealing with the church age. The two dealings are distinct and have vast differences, so what looks like contradiction is actually different contexts.
Les explains that apparent contradictions arise because in one instance God is dealing with Israel, and in another instance He is dealing with the church age, and there are vast differences between those dealings. He also points out that Romans 9, 10, and 11 are parenthetical chapters in the middle of Romans where Paul digresses to deal with the Jew. Romans 9 deals with Israel's past, Romans 10 deals with God's dealing with Israel in the present, and Romans 11 deals with Israel's future. Afterward, the flow returns to where Romans 8 left off and then goes into chapter 12.