Romans 11:2-4 — God hath not cast away His people which He foreknew. Wot ye not what the scripture saith of Elijah? how he maketh intercession to God against Israel saying,
Lord, they have killed Thy prophets, and digged down Thine altars; and I am left alone, and they seek my life.
But what saith the answer of God unto him? I have reserved to myself seven thousand men, who have not bowed the knee to the image of Baal.
Answer 2 — God has foreknowledge and knew how Israel would respond, but He still made promises.
Answer 3 — God always preserves a remnant of believers (1 Kings 19:10, 14, 18).
maketh intercession against — plead against
"to Myself" — added to the original quote by Paul to emphasize God's power and will in election.
cast away — Rejected, thrust from ones self.