The disciples expected that Christ would "come" as King, with a royal presence, and to remove the Romans and thrown down the corrupt temple, all at the same time and soon! It was a disappointment for them it turned not out that way, but they came to understand we could have an even much better future because of what Jesus had done. Though they also became convinced of the necessity to be prepared for the time that Jesus would return and that each believer could add by his effort of preaching, to bring the time closer.
We have 66 books that have been collected which bring us words from many ordinary people, but also from special people chosen by God, prophets and Words of God Himself, who bring us the beginning and the end of the world. In the infallible Word of God, the Bible we also find the announcing formerly of several but also about the last things still to come, before their taking place, and are completed. Being able to see how in the past those prophesies came true we should come to see how all the counsel of God will stand, and all as much as He has planned He did and will do also for the future. The bible is the Book which offers the best doctrine and is the best source for getting the best instruction and for getting understanding and wisdom.