Prior to the total resurrection, the Final Day of Judgement or Reckoning, there will be a period of Raj'at or Qiyamate Sughra i.e. Partial resurrection wherein the Holy Prophet (S) and the Ahle Bait (A), a group of people perfect in faith and belief, and a group of extremely wicked people will be brought to life again. This will take place during the period when the expected and the awaited Imam Mahdi (A), the twelfth and the last successor of the Holy Prophet (S) will appear on this earth.
Imam Ja'far as Sadiq (A) says: "He who does not believe in our Raj'at (return) is not from us." Thus belief in Raj'at is an article of faith.
Islam demands a Muslim to essentially believe in the return of every thing to the Lord for the Final Judgement of every soul with regard to its faith and actions. There are repeated declarations in the Holy Qur'an, informing man of this Day and warning him to be on guard in this life on earth, against the Requital which is sure and certain to take place. It is the conviction about this fact that would keep man, on the right path, duly guarded against his accountability. It is natural that when an individual is not mindful of his or her accountability, nothing would stop him or her, to commit any sin or crime and with the sense of one's accountability one would never dare to exceed the limits, and would always remain guarded.
A Muslim should and must believe in Qiyamah and live such a clean life which would help him to pass the Divine Judgement easily and earn the life eternal of the heavenly bliss. The fifth principle of the faith is the belief in Qiyamah. The faith in this principle is compulsory.
Every human being is individually accountable for each one's faith and deeds. The Holy Qur'an declares:
"And for all according to what they did; and that He may fully recompense their deeds, "and they shall not be done any injustice." (al Ahqaf, 46:19)
After death, all human beings will be resurrected to be rewarded and punished according to each individual's earnings of virtue and vice in this life. "The present life is only a season for cultivation or effort, and the life after death will be the period of harvest or the result. This life, is for creating causes for effects in the hereafter. As one sows now, so then shall be reap.
FIRST AND SECOND TRUMPETS
The sound of the trumpet will be the first stage of the Day of Judgement. Allah has mentioned it in many ayats of the Holy Qur'an. An example of such an ayat :
" And the Trumpet shall be blown, then shall swoon (die) whoever is in heavens and whoever is in the earth,. Then the (Trumpet) shall be blown again and lo! they shall stand up awaiting (they shall wake up again)." (39:68)
So the trumpet will be blown twice. When it will be blown for the first time, people (and every living thing) will die. After it is blown for the second time, everyone will wake up and indeed it will be the Day of Judgement.
Imam Zainul Abedeen (A) was asked : "How much time will pass between the two blowings of the trumpet ? He said : "As much as Allah would please." Then he was asked : "Then please tell me, O Son of the Messenger of Allah, how the trumpet will be blown?" The Imam (A) said :
"So far as the first blowing is concerned, verily Allah will command angel Israfil, who will come towards the earth, and with him will be a Trumpet; and the Trumpet will have one mouth-piece and two tubes; and the space between the two tubes will be like that between the sky and earth."
When the angels will see Israfil descend towards the earth with his Trumpet, they will say, 'Verily, Allah has ordered the inhabitants of earth to die, and the inhabitants of heaven to die.'
Then Israfil will blow the trumpet once; and the voice will come out of that side which is towards the earth and all living beings on the earth will die; and then the voice will come out from the side which is towards the heaven, and all living things in the heavens will die.
Then Allah will say to Israfil : 'O Israfil, die.' And he will die too. And they will remain like this as long as Allah would wish.
The Imam (A) continues :
"Then Allah will create a loud voice which will be heard throughout the earth and the heaven : 'Whose is the Kingdom this day ?'. No one will give any answer (as there will be none alive); then He will answer Himself creating a loud voice: 'It is Of Allah, the One, the Subduer (Holy Qur'an 40:16); I subdued all the creatures and gave them death; verily, I am Allah, there is no God except I alone, there is no partner for me and I made the creatures by my power and I made them die by My will; and I shall resurrect them by my Power.
"Then Allah (whenever he decides) will cause the second blowing of the Trumpet; the voice will come out from the side which is towards the heavens; inhabitants there will become alive and will stand as before, and the same wil happen to the people of the earth. People will now be gathered for reckoning (giving accounts of their good and bad deeds). It is indeed the Day - the Day of Judgement or Qiyamah.