Why is the present church age a parenthesis?

Les teaches that the church, which is His body, is called out during this present interval while Israel has been in dispersion—out of the land, without a temple, and without a sacrifice. It is a parenthetical period. The church must be called out of the way because God is going to pick up where He left off with the Jew. When the church is removed, God can resume His dealings with Israel, since law and grace cannot be mixed. The age of grace will be consummated and taken out at the rapture. Believers meet Christ in the air and go back with Him into heaven, while the seven years of tribulation rage on the earth. After the rapture, receiving new bodies, they step out of time and into eternity.