Why did some martyrs feel pain, and why did 'Umar (may Allah be pleased with him) not see his abode in Paradise when he was martyred, and is seeing one's seat in Paradise exclusive to those who are martyred only while striving in jihad?

A martyr has many virtues, among them: that he is forgiven with the first gush of his blood, he sees his seat in Paradise, he is adorned with the ornament of faith, he is protected from the torment of the grave, he is secured from the Great Terror, a crown of dignity is placed upon his head, and he intercedes for seventy of his household. The martyr does not feel the pain of being killed except as one of us feels the prick of a gnat.

The story narrated by Abu Hurayrah about the man who was killed, he was Qazmān, and he was among the hypocrites. He killed himself after suffering severe wounds, for he could not bear them, and his fighting was not for the sake of religion.

As for Umar ibn al-Khaṭṭāb and Uthmān ibn Affān, may Allah be pleased with them, they are counted among the martyrs.

As for the man who cut off his fingers, he is not a martyr; rather, he killed himself. Allah has forgiven him and admitted him into Paradise. This is an evidence that whoever kills himself or commits a sin and dies without repentance is not a disbeliever, and his affair is up to Allah the Almighty.