Allah said,

﴿وَلاَ تَقْتُلُواْ النَّفْسَ الَّتِى حَرَّمَ اللَّهُ إِلاَّ بِالْحَقِّ﴾

(And kill not anyone whom Allah has forbidden, except for a just cause (according to Islamic law).) This part of the Ayah emphasizes this prohibition in specific, although it is included in the immoral sins committed openly and in secret. In the Two Sahihs, it is recorded that Ibn Mas`ud said that the Messenger of Allah said,

«لَا يَحِلُّ دَمُ امْرِىءٍ مُسْلِمٍ يَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللهُ وَأَنِّي رَسُولُ اللهِ، إِلَّا بِإِحْدَى ثَلَاثٍ: الثَّيِّبُ الزَّانِي، وَالنَّفْسُ بِالنَّفْسِ، وَالتَّارِكُ لِدِينِهِ الْمُفَارِقُ لِلْجَمَاعَة»

(The blood of a Muslim person who testifies that there is no deity worthy of worship except Allah and that I am the Messenger of Allah is prohibited, except for three offenses: a married person who commits illegal sexual intercourse, life for life, and whoever reverts from the religion and abandons the Jama`ah (the community of faithful believers).) There is a prohibition, a warning and a threat against killing the Mu`ahid, i.e., non-Muslims who have a treaty of peace with Muslims. Al-Bukhari recorded that `Abdullah bin `Amr said that the Prophet said,

«مَنْ قَتَلَ مُعَاهِدًا لَمْ يَرَحْ رَائِحَةَ الْجَنَّةِ، وَإِنَّ رِيحَهَا لَيُوجَدُ مِنْ مَسِيرَةِ أَرْبَعِينَ عَامًّا»

(Whoever killed a person having a treaty of protection with Muslims, shall not smell the scent of Paradise, though its scent is perceived from a distance of forty years. ) Abu Hurayrah narrated that the Prophet said,

«مَنْ قَتَلَ مُعَاهِدًا لَهُ ذِمَّةُ اللهِ وَذِمَّةُ رَسُولِهِ فَقَدْ أَخْفَرَ بِذِمَّةِ اللهِ، فَلَا يَرَحْ رَائِحَةَ الْجَنَّةِ، وَإِنَّ رِيحَهَا لَيُوجَدُ مِنْ مَسِيرَةِ سَبْعِينَ خَرِيفًا»

(Whoever killed a person having a treaty of protection with the Muslims, and who enjoys the guarantee of Allah and His Messenger, he will have spoiled the guarantee of Allah ﴿for him﴾. He shall not smell the scent of Paradise though its smell is perceived from a distance of seventy years.) Ibn Majah and At-Tirmidhi recorded this Hadith, and At-Tirmidhi said, "Hasan Sahih.'' Allah's statement,

﴿ذلِكُمْ وَصَّـكُمْ بِهِ لَعَلَّكُمْ تَعْقِلُونَ﴾

(This He has commanded you that you may understand.) means, this is what He has commanded you that you may comprehend His commandments and prohibitions.

﴿وَلاَ تَقْرَبُواْ مَالَ الْيَتِيمِ إِلاَّ بِالَّتِى هِىَ أَحْسَنُ حَتَّى يَبْلُغَ أَشُدَّهُ وَأَوْفُواْ الْكَيْلَ وَالْمِيزَانَ بِالْقِسْطِ لاَ نُكَلِّفُ نَفْسًا إِلاَّ وُسْعَهَا وَإِذَا قُلْتُمْ فَاعْدِلُواْ وَلَوْ كَانَ ذَا قُرْبَى وَبِعَهْدِ اللَّهِ أَوْفُواْ ذَلِكُمْ وَصَّـكُمْ بِهِ لَعَلَّكُمْ تَذَكَّرُونَ ﴾

(152. "And come not near to the orphan's property, except to improve it, until he (or she) attains the age of full strength; and give full measure and full weight with justice." -- We burden not any person, but that which he can bear -- "And whenever you speak, say the truth even if a near relative is concerned, and fulfill the covenant of Allah. This He commands you, that you may remember.")