Martyrs of Karbala - a distinctive perspective

The Holy Quran says:
'We said: O fire! be a comfort and peace to Ibrahim!' (21:59)

Jabir narrates from Imam al-Baqir [a]:'Before his martyrdom, Imam al-Husayn bin Ali [a] said to his companions:
Indeed the Apostle of Allah [s] said [to me]:
O my dear young son, surely you will be led to ‘Iraq; it is a land where Prophets of Allah and Successors of the Prophets have met; It is a land called Amura.
And indeed you shall be martyred there together with a group among your companions who would not sense the pain of the touch of iron.
Then Imam al-Husayn [a] read the  verse: ‘O Fire, be cool and peaceful for Ibrahim’ (21:59). The war will be cool and peaceful on you and them.'
(Qutb al-Din al-Rawandi, al-Khara'ij wa al-Jarayih, v.2, p. 848)

Explaining this situation of the Imam, the grand Ayatullah Jawadi Àmuli says:
According to a tradition from Imam al-Baqir [a] the army of al-Husayn [a] did not feel the pain of the blows and wounds on ‘Ashura’ day save a pinch...why is that?
This is because the spirit is the origin of pain and happiness.
One of you may fast and feel the pangs of hunger and thirst...
whereas another would fast but we would find in him nothing but happiness and high-spiritedness...aren’t the physical conditions similar for both?
So why is the first in torment while the second does not feel anything?
This is because the spirit of the second is attached to a realm distant from the material conditions.
Indeed the gallant warriors of Karbala were among those great spirits overcome by the unseen plane of existence.
(Ayatullah Jawadi Amuli, Thawrat al-’Ishq al-Ilahi, p. 232)
Shaykh Muhammad Khalfan; The Sacred Effusion

Muhammad bin Marwan is reported to have said:

I heard him Imam al-Sadiq [a] say:
Visit al-Husayn [a], even if it is once a year, for whosoever comes to him, with knowledge of his station, and not a nonbeliever, would not be given other than Paradise, and he would bebestowed with extensive sustenance, and Allah would quickly relieve him (from his problems).
Indeed Allah entrusted four thousand angels on the grave of al-Husayn [a], all of who weep for him.
They accompany the visitor until he returns to his family, and if the visitor gets sick they visit him, and if he dies, they witness his bier and seek for his forgiveness and mercy.
Ibn Qulawayh, Kamil al-Ziyarat, pp. 175-176