In The Name of Allaah, The Most Merciful, The Bestower of Mercy.

Imaam As-Sadi [may Allaah have mercy upon him] said:

What the Islamic Sharee’ah brought regarding prescribed punishments and their different types depending on the severity of the crimes: crimes and transgressions committed against Allaah’s rights and the rights of Allaah’s servants are among the greatest acts of wrong doing that violates social order as well as the religious and worldly affairs. So, Allaah legislated punishments for crimes as a deterrent and lessen its burdens through capital punishment, flogging and various types of punishments. All of them have benefits – specific and general affairs of public welfare by way of which the sensible person knows the excellence of the Sharee’ah, and that evils cannot be fully resisted and repelled, except through the Sharee’ah punishments, which Allaah prescribed for different crimes depending on how prevalent, rare, severe or less severe they are. (1) [End of quote]

Read here: Sharī’ah Law and its place in Islam (Ethics 1.2) – By Shaikh Abu Khadeejah [may Allaah preserve him]: https://abukhadeejah.com/educate-yourself-ethics-1-2-shariah-redstone-academy/

One of The Many Noble Reasons Behind Capital Punishment

Allaah [The Exalted] said:

يَـٰٓأَيُّہَا ٱلَّذِينَ ءَامَنُواْ كُتِبَ عَلَيۡكُمُ ٱلۡقِصَاصُ فِى ٱلۡقَتۡلَى‌ۖ ٱلۡحُرُّ بِٱلۡحُرِّ وَٱلۡعَبۡدُ بِٱلۡعَبۡدِ وَٱلۡأُنثَىٰ بِٱلۡأُنثَىٰ‌ۚ فَمَنۡ عُفِىَ لَهُ ۥ مِنۡ أَخِيهِ شَىۡءٌ۬ فَٱتِّبَاعُۢ بِٱلۡمَعۡرُوفِ وَأَدَآءٌ إِلَيۡهِ بِإِحۡسَـٰنٍ۬‌ۗ ذَٲلِكَ تَخۡفِيفٌ۬ مِّن رَّبِّكُمۡ وَرَحۡمَةٌ۬‌ۗ فَمَنِ ٱعۡتَدَىٰ بَعۡدَ ذَٲلِكَ فَلَهُ ۥ عَذَابٌ أَلِيمٌ۬
وَلَكُمۡ فِى ٱلۡقِصَاصِ حَيَوٰةٌ۬ يَـٰٓأُوْلِى ٱلۡأَلۡبَـٰبِ لَعَلَّڪُمۡ تَتَّقُونَ

O you who believe! Al-Qisas (the Law of Equality in punishment) is prescribed for you in case of murder: the free for the free, the slave for the slave, and the female for the female. But if the killer is forgiven by the brother (or the relatives, etc.) of the killed against blood money, then adhering to it with fairness and payment of the blood money, to the heir should be made in fairness. This is an alleviation and a mercy from your Lord. So after this whoever transgresses the limits (i.e. kills the killer after taking the blood money), he shall have a painful torment. And there is (a saving of) life for you in Al-Qisas (the Law of Equality in punishment), O men of understanding, that you may become pious. [Surah Al-Baqarah. Verses 178-179]

Ash-Shaybaan reported from Qataadah who said: Among the people of the pre-Islamic era were those who transgressed and followed shaytaan. If a person had strength and a great number of supporters, and a slave of theirs is murdered by a slave of another people, then out of wanting to show their superior strength, they would say, ‘We shall not kill (by way of revenge) except a free person amongst them’. And if a woman kills another woman from another tribe, they said, ‘We shall not kill (by way of revenge) except a man amongst them’”. So, Allaah revealed this Aayah.

And regarding the statement: [وَلَكُمۡ فِى ٱلۡقِصَاصِ حَيَوٰةٌ۬ يَـٰٓأُوْلِى ٱلۡأَلۡبَـٰبِ لَعَلَّڪُمۡ تَتَّقُونَ – And there is (a saving of) life for you in Al-Qisas (the Law of Equality in punishment), O men of understanding, that you may become pious], Az-Zujaaj said, “If a man knows that he’ll be killed if he murders someone, he will refrain from murder and thus both his life and that of others are preserved. [An Excerpt from Zaadul Maseer Fee Ilmit Tafseer. By Imaam Ibnul Jawzi (rahimahullaah)]

Imaam Ibnul Qayyim [rahimahullaah] said: He refrains from killing out of loving and giving precedence to his own life, so there is preservation of his life and the life of the one he wants to murder. Also when a man killed another man from another family or tribe, the family or tribe of the victim killed everyone they could find from the family, tribe and city district of the murderer, and in this there was overwhelming corruption and destruction, so Allaah legislated the law of equality in punishment and so that none else is killed except the one who committed murder. This preserved the lives of murderer’s relatives and the people of his city. [An Excerpt from Miftaah Daar As-Sa’aadah 431-432. Slightly paraphrased]

Imaam As-Sadi [rahimahullaah] said: By way of it [i.e. the law of equity in punishment] life is preserved and the misguided ones who exit the confines of justice are restrained. And when others witness a murderer being executed [i.e. by the government], they will take heed and refrain from the crime of murder. So, if the punishment against a murderer was other than killing him [by way of capital punishment], the evil act of murder would not have been prevented. This is the case regarding all the prescribed punishments of the Sharee’ah, because they contain a means of prevention which shows the perfect Wisdom of The All-Wise , the Oft-Forgiving. And Allaah specifically mentioned life in this Aayah as emphasis and exaltation. And when it is the case that none knows the reality of this ruling except the people of sound intellect and strong understanding, Allaah addressed them specifically. [An Excerpt from Tafseer as-Sadi. Slightly paraphrased]

Ruling By Other Than What Allaah Has Revealed: A Treatise on Ruling by Other than What Allaah has Revealed- By Shaikh `Abdus-Salam al-Burjis [may Allaah have mercy upon him]: http://www.salafipublications.com/sps/sp.cfm?subsecID=MNJ05&articleID=MNJ050003&pfriend=

Believer’s Bahaviour Towards Muslim Rulers: https://salaficentre.com/2021/02/10/believers-bahaviour-towards-muslim-rulers-advise-given-in-private-supplicate-for-them-and-refrain-from-rebellion-so-beware-of-spiteful-foreign-instigators-and-some-dangerous-social-media-networ/

Our Responsibilities Whilst Living in a Society That Rules By Secular Laws

Shaikh Abdul Waahid Abu Khadeejah [may Allaah preserve him] said: Although Muslims in Britain are subject to British law and the British legal system, Sharī’ah tribunals are allowed in certain areas as an alternative way of resolving disputes. These are aimed at resolving commercial, civil and matrimonial disputes to the satisfaction of both sides. Sharī’ah Law is based upon the Qur’ān and Sunnah, and judgements are made in accordance to these two sources. Only those well-versed with the Religion and jurisprudence (rulings in law) are permitted to judge in Sharī’ah matters. Read more here: https://www.abukhadeejah.com/educate-yourself-ethics-1-2-shariah-redstone-academy/

NB: Shaikh Abu Khadeejah stated, “Muslims in Britain are subject to British law and the British legal system”. Therefore, one must be well aware of this fact and distance himself from the Takfeeris and those who take the law into their own hands. One must pay close attention to the fact – out of fear of Allaah and the last Day – that it is obligated on us to behave well towards our non-Muslim fellow citizens and fulfil our covenants. Imaam Muhammad Ibn Saaleh Al-Uthaymeen [rahimahullaah] stated: Likewise I invite you to have respect for those people who have the right that they should be respected, from those between you and whom there is an agreement (of protection) [i.e. Non-Muslims]. For the land which you are living is such that there is an agreement between you and them. If this were not the case they would have killed you or expelled you. So preserve this agreement, and do not prove treacherous to it, since treachery is a sign of the hypocrites, and it is not from the way of the Believers. And know that it is authentically reported from the Prophet that he said : “Whoever kills one who is under an agreement of protection will not smell the fragrance of Paradise.” Do not be fooled by those sayings of the foolish people: those who say: ‘Those people are Non-Muslims, so their wealth is lawful for us [i.e. to misappropriate or take by way of murder and killing].’ For by Allaah – this is a lie. A lie about Allaah’s Religion, and a lie in Islamic societies.

O my brothers. O youth. O Muslims. Be truthful in your buying and selling, and renting, and leasing, and in all mutual transactions. Because truthfulness is from the characteristics of the Believers, and Allaah – the Most High – has commanded truthfulness – in the saying of Allaah – the Most High – “O you who believe – fear and keep you duty to Allaah and be with the truthful.”

And the Prophet encouraged truthfulness and said : “Adhere to truthfulness, because truthfulness leads to goodness, and goodness leads to Paradise; and a person will continue to be truthful, and strive to be truthful until he will be written down with Allaah as a truthful person“.

And he warned against falsehood, and said : “Beware of falsehood, because falsehood leads to wickedness, and wickedness leads to the Fire. And a person will continue lying, and striving to lie until he is written down with Allaah as a great liar.”

O my brother Muslims. O youth. Be true in your sayings with your brothers, and with those Non-Muslims whom you live along with – so that you will be inviters to the Religion of Islaam, by your actions and in reality. So how many people there are who first entered into Islaam because of the behaviour and manners of the Muslims, and their truthfulness, and their being true in their dealings. [Salafipublications.com]

Must Read: Living With Non-Muslims With Fine Conduct:

https://www.abukhadeejah.com/living-with-non-muslims-in-the-west-with-fine-conduct/
https://www.abukhadeejah.com/wp-content/uploads/2014/12/Living-with-Non-Muslims.pdf

Alliance with the non-Muslims is of two types – misunderstanding this affair leads people astray
https://www.abukhadeejah.com/having-alliance-with-the-non-muslims-is-of-two-types-misunderstanding-this-affair-leads-people-astray/

Treaties With The Non-Muslims: Is it Allegiance? Is it Apostasy?
https://www.abukhadeejah.com/treaties-with-the-non-muslims-do-they-necessitate-allegiance/

The Prophet of Islam would not kill diplomats, ambassadors, emissaries or foreign delegations even if they were sent by the worst of his enemies
https://www.abukhadeejah.com/the-prophet-of-islam-would-not-kill-diplomats-ambassadors-emissaries-or-foreign-delegations-even-if-they-were-sent-by-the-worst-of-his-enemies/

[Ref 1: Ad-Durra Al-Mukhtasar Fee Mahaasin Deen Al-Islaamiy page 29 slightly paraphrased]