A proper dispensational understanding of the Bible (2 Timothy 2:15) absolutely necessitates a pre-tribulational Rapture of the Church.
What is the Church? The Church is being formed during the present Dispensation of Grace and is comprised of all who believe, whether Jew or Gentile, who are subsequently baptized into the Body of Christ (1 Corinthians 12:12-13). Furthermore, the Church is not (the nation of) Israel, or any other nation, but a unique body comprised of believers from all nations. However, if the Church is present on earth during the Tribulation period (i.e., the 70th Week of Daniel; Daniel 9:27), all who believe during the Tribulation must become members of the “Church”. If this is to be the case, there can be no “saved” nation of Israel or Gentile nations present on earth at the end of the Tribulation to enter the Millennial Kingdom.
Utter confusion results if the Church is present on earth during the Tribulation. But thanks be to God, who has promised to remove the completed Church, the Body of Christ, at the Rapture (e.g., 1 Thessalonians 1:10; 2 Thessalonians 2:3; Revelation 3:10). During the Tribulation, the Church will be wed to Christ in heaven (Revelation 19:7-8), and those on earth who believe and endure to the end make up the “saved” nations who enter the Millennial Kingdom at the second coming of Christ.