All praise is due to Allah, and may peace and blessings be upon the Messenger of Allah.
The religious texts describe the taking of souls in two circumstances:
The angels of mercy take their souls and give them glad tidings of Allah’s mercy and Paradise. Allah Almighty says:
“Those whose souls the angels take while they are in a state of purity, saying, ‘Peace be upon you! Enter Paradise because of what you used to do.’” [An-Nahl 16:32]
The angels of punishment take their souls with severity and threats. Allah Almighty says:
“If only you could see when the angels take the souls of those who disbelieve, striking their faces and their backs.” [Al-Anfal 8:50]
As for a sinful Muslim or someone who commits major sins, there is no explicit text that definitively establishes whether the angels of mercy or the angels of punishment take his soul, because this matter belongs to the unseen.
One piece of evidence illustrating the seriousness of the situation of someone who commits major sins is the story of the man who killed one hundred people and then repented. The angels of mercy and the angels of punishment disputed over him. The angels of mercy said that he had come to Allah in repentance, while the angels of punishment said that he had never done any good. It was then decreed that he would be among those shown mercy because of the sincerity of his repentance, as authentically reported in Sahih al-Bukhari and Sahih Muslim.
Some narrations concerning the taking of the soul also describe a wicked person as experiencing the severity experienced by evildoers. However, the term “wicked person” in these narrations may refer to a disbeliever, reconciling these reports with other narrations.
Therefore, the condition of a sinful Muslim varies according to his faith, deeds, and sins. If he is a person who believes in the oneness of Allah and remains steadfast, and his good deeds outweigh his bad ones, it is hoped that he will receive the glad tidings and mercy promised to the people of faith. Whoever mixes righteous deeds with bad deeds may be deprived of some of the glad tidings and the pleasantness of that moment in proportion to his sins.
For this reason, it is not correct to state with certainty that the angels of mercy or the angels of punishment will take the soul of a particular individual without evidence. Rather, every Muslim must fear the consequences of sin and hasten to repent and remain steadfast in obedience to Allah.
And Allah Almighty knows best.