Salam
The concept of Rajaat is in Surah Naml. The hadiths expand on it.
Even if say it means disbelief of a disbeliever being more severe implies there will be a disbeliever or more, we can gather the rajaat is supposed to happen AFTER Isa (a) dies. That is there will be a period of time before Isa (a) dies, that all will be believers.
There is disbelief before the Rajat and after Rajat. But after Rajat it is more severe. So, If you are saying that, Christ dies before Rajat, that still means there are disbelievers in Christ (before His death).
But, beside this, it is not true that Rajat is after Christ's Death, because according to Hadithes, the Rajat starts while the Qaim has rised and the Christ prays behind the Qaim. So, it means, when Christ is alive, the Rajat started.
Beside that, you did not answer the three questions I asked. Answering those three questions is the key to understand the timelines of the events, and their meaning.
Anyways, I will answer them myself.
Let me ask you a couple question about the Hadith first.
Amirul Momineen (a.s.) used to say:
I quote the Hadith again.
The first part of Hadith is:
“Someone asked: O Amirul Momineen (a.s.), is there life before Resurrection, and then death after that?"
Question 1. What is the "life" before Resurrection that, he is referring?
What "death" is he talking about in the context of the Hadith?
The life before Resurrection is a reference to the Qaim resurrecting the Dead"
اعلموا أن الله يحيي الارض بعد موتها قد بينا لكم الآيات لعلكم تعقلون)] (الحديد - 17). حياة الارض بعدل المهدي عليه السلام بعد موتها بالجور [1875 - (الامام الباقر عليه السلام) " يحييها الله عزوجل بالقائم عليه السلام، بعد موتها، بموتها: كفر أهلها، والكافر ميت
Imam Muhammad Baqir (a.s.) said: “Allah, the Exalted will revive it through the Qaim after its death; its death implies disbelief of its inhabitants, Lbecause the disbelievers are dead.”
That means, before Qaim rises, a Death has come. Then, through the Qaim a life is given. By "Death" is meant "Disbelief, and by "Life" is meant "Belief".
Thus the Metaphorical meaning of the death and alive becomes clear.
Question 2: how does this person know that there is a life before Qiyamat and then a death after it?
Where did he get this knowledge from?
Do you know?
He knew that there is a life before Qiyamat from verse 17 of Surah الحديد, which I quote again
اعلموا أن الله يحيي الارض بعد موتها قد بينا لكم الآيات لعلكم تعقلون)] (الحديد - 17). حياة الارض بعدل المهدي عليه السلام بعد موتها بالجور [1875 - (الامام الباقر عليه السلام) " يحييها الله عزوجل بالقائم عليه السلام، بعد موتها، بموتها: كفر أهلها،
And, he knew, there is a Death, after the first life from verse 40:11,
قَالُوا رَبَّنَا أَمَتَّنَا اثْنَتَيْنِ وَأَحْيَيْتَنَا اثْنَتَيْنِ فَاعْتَرَفْنَا بِذُنُوبِنَا فَهَلْ إِلَىٰ خُرُوجٍ مِّن سَبِيلٍ
"They will say, 'Our Lord, You made us lifeless twice and gave us life twice, and we have confessed our sins. So is there to an exit any way?'" (Quran 40:11).
He knew by counting the number of Deaths and Lives. There was a Death before the Qaim Rises, as understood from الحدید 17, then a Life comes through the Qaim. Then after this first life, there must be another Death, so, we can count twice Death and then comes the Qiyamat, which is the second life. Hence the verse says, twice Death, and twice Life.
The secod life, is the life given through Return of Christ.
Now, notice carefully about what Ali answered:
"He replied: Yes, by Allah, disbelief after the Rajat is more severe than disbelief before it."
Question 3. Here the person asking Ali about life and death related to before Qiyamat and Ali replys "yes", but immediately after He replies yes, it appeas as if He is changing the topic. Now, He talks about "disbelief". How does the question about Life and Death before Resurrection, has anything to do with the reply from Ali which is about "Disbelief"?
So, why Ali talked about "Disbelief", when the question was about "death"?
Its relation becomes clear when one considers that "Death" is metaphor for "Disbelief", as this Hadith tells us:
تُولِجُ ٱلَّيْلَ فِى ٱلنَّهَارِ وَتُولِجُ ٱلنَّهَارَ فِى ٱلَّيْلِ ۖ وَتُخْرِجُ ٱلْحَىَّ مِنَ ٱلْمَيِّتِ وَتُخْرِجُ ٱلْمَيِّتَ مِنَ ٱلْحَىِّ ۖ وَتَرْزُقُ مَن تَشَآءُ بِغَيْرِ حِسَابٍۢ
"You cause the night to enter the day, and You cause the day to enter the night; and
You bring the living out of the dead, and You bring the dead out of the living. And You give provision to whom You will without account." (Quran 3:27).
- حدثنا الحسن بن يحيى قال : أخبرنا عبد الرزاق قال : أخبرنا معمر قال : قال الحسن في قوله : " تخرج الحي من الميت وتخرج الميت من الحي " قال : يخرج المؤمن من الكافر ، ويخرج الكافر من المؤمن .
عَنْ أَبِي عَبْدِ اللَّهِ
فَالْحَيُّ الْمُؤْمِنُ الَّذِي تَخْرُجُ طِينَتُهُ مِنْ طِينَةِ الْكَافِرِ وَ الْمَيِّتُ الَّذِي يَخْرُجُ مِنَ الْحَيِّ هُوَ الْكَافِرُ الَّذِي يَخْرُجُ مِنْ طِينَةِ الْمُؤْمِنِ فَالْحَيُّ الْمُؤْمِنُ وَ الْمَيِّتُ الْكَافِرُ وَ ذَلِكَ قَوْلُهُ عَزَّ وَ جَلَّ- أَ وَ مَنْ كانَ مَيْتاً فَأَحْيَيْناهُ[5] فَكَانَ مَوْتُهُ اخْتِلَاطَ طِينَتِهِ مَعَ طِينَةِ الْكَافِرِ وَ كَانَ حَيَاتُهُ حِينَ فَرَّقَ اللَّهُ عَزَّ وَ جَلَّ بَيْنَهُمَا بِكَلِمَتِهِ كَذَلِكَ يُخْرِجُ اللَّهُ عَزَّ وَ جَلَّ الْمُؤْمِنَ فِي الْمِيلَادِ مِنَ الظُّلْمَةِ بَعْدَ دُخُولِهِ فِيهَا إِلَى النُّورِ وَ يُخْرِجُ الْكَافِرَ مِنَ النُّورِ إِلَى الظُّلْمَةِ بَعْدَ دُخُولِهِ إِلَى النُّورِ-
According to these Hadithes and many others "Dead" is a metaphor for "Disbeliever"
And to conclude i will quote another similar verse
وقال الله عز وجل: " يخرج الحي من الميت ومخرج الميت من الحي
[4] " فالحي: المؤمن الذي تخرج طينته من طينة الكافر والميت الذي يخرج من الحي: هو الكافر الذي يخرج من طينة المؤمن فالحي: المؤمن، والميت: الكافر وذلك قوله عز وجل: " أو من كان ميتا فأحييناه
[5]
This Hadith is from Imam Sadiq. With regards to the verse 30:19 (He brings the Dead out of living....), Imam said, it means, the 'believer is the living', and the 'disbeliever is the dead'...He will cause the attributes of believer to appear in a disbeliever!
Now, here is the complete verse:
"He brings forth the living from the dead and the dead from the living. He gives life to the earth after its death, and
you shall be raised to life in the same way." 30:19
Notice the bolded part! And think rising to life means what!