Everyone in this world is well aware of the fact that this life is mortal. All of us are sent into this world for some specific time after that we have to dwell in eternal life which starts after the end of this life.

Humans pass through different phases after death i.e. separation of the soul from body, life, in the grave and the most important event that will happen on the Day of Judgment is when we will be held accountable for our deeds and when we will be questioned by our Lord Allah (S.W.T.) as He says in Quran:

Then surely, We shall question those (people) to whom it (the book) was sent and verily, We shall question the Messengers.” ( Al-Araf, 6 and 7)

Two Methods of Accountability
On the Day of Judgment, every human being who is sent into this world in any era will be stood together at a place where they will be held accountable in front of God as He says in the Quran:

The Day is approaching when every soul shall find itself confronted with whatever good it has done and whatever evil it has wrought. It will then wish there is a wide space between it and the Day! Allah warns you to beware of Him; He is most tender towards His servants.” (Surat Al-Imran, 30)

There will be two methods of accountability,

Those who have successfully spent their lives according to the teachings of Allah and His Prophet (PBUH) will be directly sent to paradise to live an eternal life with all the blessings they have been promised and will be considered the most successful people.

They will say: “Praise be to Allah Who has fulfilled His promise to us and made us the inheritors of this land, letting us settle in Paradise wherever we want. How excellent is the wage of those who work.” (Surat az-Zumar, 74)

Those who used to commit evil things in the worldly life will be questioned about their bad acts and surely they will have no answer for it except shame on their own deeds and begging pardon for their wrongdoings but the time of forgiveness will be over. Those people will be sent to hell fire where they will be tortured for their sins until they complete their punishments.

On the Day when those who were unbelievers are exposed to the Fire, [it will be said to them]: “You dissipated the good things you had in your worldly life and enjoyed yourself in it. So today you are being repaid with the punishment of humiliation for being arrogant on the earth without any right, and for being deviators.” (Surat al-Ahqaf, 20)

First Question for the Mankind
Prayer is the very first question that will be asked from the people on the Day of Judgment. If a person performs prayers with extreme quality, then the person will be saved.

If the prayers were done incompletely or half-heartedly, then his voluntary prayers will suffice for the shortcomings.

Prophet (PBUH) said:

The Messenger (S.A.W.) told us in an authentic hadith , “The first thing the people will be accountable for on the Day of Judgment is prayer, Allah will say to His angels (even though he already knows): “Look at my servant’s prayers. Were they complete or not?” If they were complete it will be written as complete. If they were not fully complete Allah will say: “See if my servant has voluntary prayers, if he has them Allah will say: Complete his obligatory prayers shortage with his voluntary prayers.” Then the rest of his deeds will be dealt with in the same manner.

(Reported by Imams Ahmad, Abu Dawood, An-Nisa’i, and Al-Hakim)

Five Things that will be Asked
The prophet Muhammad (PBUH) told us about five major questions that will be asked, and no one can bypass these prosecutions.

How he lived his life?
How he utilized his youth?
What means did he earn his wealth?
How did he spend his wealth?
What did he do with his knowledge?

There are lots of other questions that will be asked of us e.g. all of our covenants and promises that have been made in our lives, hearing, our vision, and our hearts.

And fulfill (every) covenant. Verily! The covenant will be questioned about.” ( Surat Al-Israa, Verse 34)

Verily! The hearing, and the sight, and the heart, of each of those, you will be questioned (by Allah)” ( Surat Al-Israa, Verse 36)

Conclusion
Muslims should consider themselves very lucky by having been told about the day of judgment in such clear words and having Quran, Hadith, and Sunnah to learn and live life according to them so that on the Day of Judgment we stand amongst the believers and successful people.

The good believer is the one who prepares himself for those difficult events by getting closer to Allah (S.W.T), by doing good deeds, and by staying away from what Allah has forbidden, so that he will be among those who receive their book of deeds on the Day of Judgment in their right hand and Allah will enter them into paradise.

As Allah Says in Quran ” So those on the Right Hand (i.e. those who will be given their Records in their right hands) — how (fortunate) will be those on the Right Hand! (As a respect for them, because they will enter Paradise).” (Surat -Al -Waqiya-verse- 8).

In another verse.
Then, if he (the dying person) be of the Muqarrabun (those brought near to Allah),(There is for him) rest and provision and a Garden of Delights (Paradise).And if he (the dying person) be of those on the Right Hand, Then there is safety and peace (from the Punishment of Allah) for those on the Right Hand. (Surat -Al -Waqiya-verse- 88-91)