Salvation of Israel & Gentiles

Has God cast off Israel? Has he replaced Israel with the Church of Jesus Christ? Did God speak of these things through His Prophets in the Old Testament? Will the Church go through the Tribulation under the allegorical name of "Israel?" Does salvation rest on Sovereign Election or the responsibility of man? And what about His gifts and calling? Does he change His mind? If so, does that mean the Church has replaced Israel in God's promises and long term plan of redemption? And just where do you fit into all of this? It's all here in a very passionate message driven by the love our Rescuing God!