Tafsir of Al Imran 3:157

And if you are killed or die in the way of Allah, forgiveness and mercy from Allah are far better than all that they amass. indicating that death and martyrdom in Allah's cause are a means of earning Allah's mercy, forgiveness and pleasure. This, indeed, is better than remaining in this life with its short lived delights. Furthermore, whoever dies or is killed will return to Allah, the Exalted and Most Honored, and He will reward him if he has done good deeds, or will punish him for his evil deeds. Allah said,

ولين متم أو قتلتم ﻻلى الله تحشرون