Conclusion
The history of man begins from Adam. After that, throughout long periods of history, God appointed and sent His messengers to inform man of His creation plan: what the Creator wants from him in this world; what is going to be his fate in the next world. This dawah work was performed by the prophets over a long period of time. It is mentioned in a tradition of the Prophet that more than 100,000 prophets came to the world for this purpose.
The second phase may be termed as the phase of warning of the coming of Doomsday. That is, warning people in advance of the time which is fast approaching. This warning had to be issued through the re-appearance of the Ark or daabba. It appears that this warning has been issued and now the time is not far when the period before Doomsday is over and human history on earth reaches its end.
After this, the third phase will commence with the blowing of the Trumpet by the Angel Israfil. In accordance with Islamic belief, when the time comes and the respite of action is over, and the time of judgement comes (it is all in the knowledge of God), at that time the Angel Israfil will blow the trumpet and it will, all of a sudden, herald the beginning of the final and eternal phase of human life, as we have been informed by all the prophets.
