Feast of Trumpets 2014—Christ’s Return

The Feast of Trumpets symbolizes the return of Jesus Christ and the resurrection of the righteous to eternal life. The book of Revelation contains seven messages to seven congregations of the Church of God. What relationship exists between the last four of those seven messages and Christ’s return? What does the Bible say about the time of Christ’s return? Is that time already fixed? Why does Christ say that even He does not know the exact time?  Is the time of His coming conditioned upon certain events which have to take place first? What does it mean that the time of Christ’s return is solely within the authority of the Father?