The Holy Quran says...

(39:68) The literal meaning of ‘صعق’ is to become unconscious due to a terrifying heavenly scream and sometimes it brings death to the one who hears it according to the commentators who have interpreted this verse. According to this verse, before Qiyamat the trumpet would be blown twice; on the first time, all the people present in the world would die and enter the world of Barzakh. And the second time all those who are in Barzakh would be enlivened and raised for Qiyamat.

The first time it would be to warn the people and prepare them for Qiyamat. During this first time all the inhabitants of the earth and the heavens would swoon due to its terror. But it is not mentioned that they would die. If the phrase ‘those who are in the earth’ implied those who are not dead yet, and who live in the earth, it should have mentioned: All would die at the first blowing and join those with the other folks of Barzakh, so that they may become ready for Qiyamat.

If it implies those who had died previously and who are present in Barzakh, but since they are still attached to worldly matters and are not able to forgo their attachment, and that is why it is possible to call them as ‘those who are in the earth’; and it is also unlikely. Therefore it is necessary to consider the first blowing to be aimed at warning the people and making them ready for Qiyamat.

In the second blowing, by the natural command of the all-powerful Allah the system of matter and materiality would be destroyed and dismantled and the real exigencies of the system of cause and effect would become obvious. The inner aspects of man would become apparent.