The Prophet defined the true Muslim as one who avoids harming other Muslims with his tongue (words) and hand (actions).
Abdullah bin Amr reported: The Messenger of Allah, peace and blessings be upon him, said:
الْمُسْلِمُ مَنْ سَلِمَ الْمُسْلِمُونَ مِنْ لِسَانِهِ وَيَدِهِ
The Muslim is the one from whose tongue and hand the Muslims are safe.
Source: Ṣaḥīḥ al-Bukhārī 10, Grade: Muttafaqun Alayhi
Amr ibn Absah reported: A man said, “O Messenger of Allah, what is Islam?” The Messenger of Allah, peace and blessings be upon him, said:
أَنْ تُسْلِمُ قَلْبَكَ لِلَّهِ وَيَسْلُمُ الْمُسْلِمُونَ مِنْ لِسَانِكَ وَيَدِكَ
That you surrender your heart to Allah and that the Muslims are safe from your tongue and hand.
Source: Shu’ab al-Imān 20, Grade: Sahih
We should be particularly careful to protect those within our own community, but the principle is not restricted only to Muslims. Rather, it applies to all humanity and even the animals.
In another narration of this tradition, the Prophet said:
الْمُسْلِمُ مَنْ سَلِمَ النَّاسُ مِنْ لِسَانِهِ وَيَدِهِ وَالْمُؤْمِنُ مَنْ أَمِنَهُ النَّاسُ عَلَى دِمَائِهِمْ وَأَمْوَالِهِمْ
The Muslim is the one from whose tongue and hand the people are safe, and the believer is the one who is trusted with the lives and wealth of the people.
Source: Sunan al-Nasā’ī 4998, Grade: Sahih
And in another narration, the Prophet said:
الإسلام أفضل مَنْ سَلِمَ النَّاسُ مِنْ لِسَانِهِ وَيَدِهِ
The best Islam belongs to those from whose tongue and hand people are safe.
Source: Musnad Aḥmad 6714, Grade: Sahih
Hasan Al-Basri, may Allah have mercy on him, said:
إِنْ سَرَّكُمْ أَنْ تَسْلَمُوا وَيَسْلَمَ لَكُمْ دِينُكُمْ فَكُفُّوا أَيْدِيَكُمْ عَنْ دِمَاءِ النَّاسِ وَكُفُّوا أَلْسِنَتَكُمْ عَنْ أَعْرَاضِهِمْ وَكُفُّوا بُطُونَكُمْ عَنْ أَمْوَالِهِمْ
If you would be pleased to be safe and for your religion to be safe for you, then restrain your hands from harming the lives of people, restrain your tongues from harming their honor, and restrain your stomachs from consuming their wealth.
Source: Makārim al-Akhlāq lil-Kharā’iṭī 379
It is not permissible in Islam to harm even a small animal like a bird, a dog, or even pig without a just cause for doing so.
Abdullah ibn Umar reported: The Messenger of Allah, peace and blessings be upon him, said:
مَنْ قَتَلَ عُصْفُورًا فَمَا فَوْقَهَا بِغَيْرِ حَقِّهَا سَأَلَ اللَّهُ عَزَّ وَجَلَّ عَنْهَا يَوْمَ الْقِيَامَةِ
If someone kills so much as a sparrow or anything larger without a just cause, then Allah the Exalted will ask him about it on the Day of Resurrection.
Source: Sunan al-Nasā’ī 4445, Grade: Sahih
In another narration, the Prophet said:
مَنْ قَتَلَ عُصْفُورًا عَبَثًا عَجَّ إِلَى اللَّهِ عَزَّ وَجَلَّ يَوْمَ الْقِيَامَةِ يَقُولُ يَا رَبِّ إِنَّ فُلَانًا قَتَلَنِي عَبَثًا وَلَمْ يَقْتُلْنِي لِمَنْفَعَةٍ
Whoever kills so much as a sparrow unjustly will have it pleading to Allah on the Day of Resurrection, saying: O Lord, he killed me for no reason, and he did not kill be for any beneficial purpose.
Source: Sunan al-Nasā’ī 4446, Grade: Hasan
Fudayl ibn Iyad, may Allah be pleased with him, said:
وَاللَّهِ مَا يَحِلُّ لَكَ أَنْ تُؤْذِيَ كَلْبًا وَلَا خِنْزِيرًا بِغَيْرِ حَقٍّ فَكَيْفَ تُؤْذِي مُسْلِمًا
By Allah, it is not lawful for you to harm a dog or a pig without a just cause, so how can you harm a Muslim?
Source: Siyar Aʻlām al-Nubalāʼ 8/427
Indeed, a true Muslim must not harm his neighbors at all, whether they are Muslims or non-Muslims, lest he be forbidden from entering Paradise.
Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said:
مَنْ كَانَ يُؤْمِنُ بِاللَّهِ وَالْيَوْمِ الْآخِرِ فَلَا يُؤْذِي جَارَهُ
Whoever believes in Allah and the Last Day, let him not harm his neighbor.
Source: Ṣaḥīḥ al-Bukhārī 6110, Grade: Muttafaqun Alayhi
In another narration, the Prophet said:
لَا يَدْخُلُ الْجَنَّةَ مَنْ لَا يَأْمَنُ جَارُهُ بَوَائِقَهُ
He will not enter Paradise whose neighbor is not secure from his evil.
Source: Ṣaḥīḥ Muslim 46, Grade: Sahih
And in another narration, the Prophet said:
أَلَا أُخْبِرُكُمْ بِخَيْرِكُمْ مِنْ شَرِّكُمْ خَيْرُكُمْ مَنْ يُرْجَى خَيْرُهُ وَيُؤْمَنُ شَرُّهُ وَشَرُّكُمْ مَنْ لَا يُرْجَى خَيْرُهُ وَلَا يُؤْمَنُ شَرُّهُ
Shall I not tell you what distinguishes the best of you from the worst of you? The best of you are those from whom goodness is expected and people are safe from their evil. The worst of you are those from whom goodness is not expected and people are not safe from their evil.
Source: Sunan al-Tirmidhī 2263, Grade: Sahih
