In the name of Allah, the Beneficent, the Merciful
Al-Nawawi records in his book Riyad us-Saliheen:
Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said:
الشُّهَدَاءُ خَمْسَةٌ الْمَطْعُونُ وَالْمَبْطُونُ وَالْغَرِقُ وَصَاحِبُ الْهَدْمِ وَالشَّهِيدُ فِي سَبِيلِ اللَّهِ
The martyrs are of five kinds: one who dies of plague, one who dies of stomach disease, one who drowns, one who dies under debris, and one who dies in the path of Allah the Exalted.
Source: Sahih Bukhari 2674, Grade: Muttafaqun Alayhi
Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said:
مَا تَعُدُّونَ الشَّهِيدَ فِيكُمْ
Who do you think is a martyr among you?
They said, “The one who is killed in the way of Allah.” He said:
إِنَّ شُهَدَاءَ أُمَّتِي إِذًا لَقَلِيلٌ
Verily, if that is so, then the martyrs among my nation are few.
They said, “O Messenger of Allah, then who are the martyrs?” He said:
مَنْ قُتِلَ فِي سَبِيلِ اللَّهِ فَهُوَ شَهِيدٌ وَمَنْ مَاتَ فِي سَبِيلِ اللَّهِ فَهُوَ شَهِيدٌ وَمَنْ مَاتَ فِي الطَّاعُونِ فَهُوَ شَهِيدٌ وَمَنْ مَاتَ فِي الْبَطْنِ فَهُوَ شَهِيدٌ
He who is killed in the way of Allah is a martyr, and he who dies a natural death in the way of Allah is a martyr, and he who dies of plague is a martyr, and he who dies of stomach disease is a martyr, and he who dies from drowning is a martyr.
Source: Sahih Muslim 1915, Grade: Sahih
Abdullah ibn Amr reported: The Prophet, peace and blessings be upon him, said:
مَنْ قُتِلَ دُونَ مَالِهِ فَهُوَ شَهِيدٌ
Whoever is killed defending his wealth is a martyr.
Source: Sahih Bukhari 2348, Grade: Muttafaqun Alayhi
Sa’eed ibn Zaid reported: The Messenger of Allah, peace and blessings be upon him, said:
مَنْ قُتِلَ دُونَ مَالِهِ فَهُوَ شَهِيدٌ وَمَنْ قُتِلَ دُونَ دِينِهِ فَهُوَ شَهِيدٌ وَمَنْ قُتِلَ دُونَ دَمِهِ فَهُوَ شَهِيدٌ وَمَنْ قُتِلَ دُونَ أَهْلِهِ فَهُوَ شَهِيدٌ
Whoever is killed protecting his wealth is a martyr, and whoever is killed protecting his religion is a martyr, and whoever is killed protecting his life is a martyr, and whoever is killed protecting his family is a martyr.
Source: Sunan At-Tirmidhi 1421, Grade: Sahih
Abu Huraira reported: A man came to the Messenger of Allah, peace and blessings be upon him, and he said, “O Messenger of Allah, what do you think if a man comes to seize my wealth?” The Prophet said:
فَلَا تُعْطِهِ مَالَكَ
Do not give up your wealth.
The man said, “What if he fights me?” The Prophet said:
قَاتِلْهُ
Then fight him.
The man said, “What if he kills me?” The Prophet said:
فَأَنْتَ شَهِيدٌ
You will be a martyr.
The man said, “What do you think if I kill him?” The Prophet said:
هُوَ فِي النَّارِ
He will be in the Hellfire.
Source: Sahih Muslim 140, Grade: Sahih
Success comes from Allah, and Allah knows best.