Our Lord holds the keys to the doors of Christian service. You don’t have to chase “key men” around if you know the Keeper of the keys.
Some who have much to say about the Sermon on the Mount are strangely silent about the Olivet discourse. They argue that nobody understands it. But a message that begins with the words “Take heed that no man deceive you” (Matthew 24:4), certainly was not meant to confuse, but to clarify.