5:33 The just retribution for those who fight GOD and His messenger, and commit horrendous crimes, is to be killed, or crucified, or to have their hands and feet cut off on alternate sides, or to be banished from the land. This is to humiliate them in this life, then they suffer a far worse retribution in the Hereafter.
5:34 Exempted are those who repent before you overcome them. You should know that GOD is Forgiver, Most Merciful.
5:35 O you who believe, you shall reverence GOD and seek the ways and means to Him, and strive in His cause, that you may succeed.
Last Week Tonight with John Oliver: Death Penalty ( BAD LANGUAGE @ 7:31, 9:26 & 11:53min)
https://www.youtube.com/watch?v=Kye2oX-b39E
10 Countries And Their Shocking Death Penalty Laws
https://www.youtube.com/watch?v=LluEqHF7HVA
What if The Death Penalty Disappeared in America?
https://www.youtube.com/watch?v=m4OmTdeFUok
From verse 34 it seems like the only time that capital punishment is justified is when someone is in the act of committing horrendous crimes, and not if they repent before you overcome them.
The Quran creates scenarios where it brings out our true convictions. If someone wants to be cruel they can find justification for it in the Quran, and if they want to be merciful they will also find justification for it in the Quran. The purpose of this life is to bring out our true convictions.
3:178 Let not the disbelievers think that we lead them on for their own good. We only lead them on to confirm their sinfulness. They have incurred a humiliating retribution.
3:154 …GOD thus puts you to the test to bring out your true convictions, and to test what is in your hearts. GOD is fully aware of the innermost thoughts.
Numerically Structured Books
83:7 Indeed, the book of the wicked is in Sijjeen.
16:125 You shall invite to the path of your Lord with wisdom and kind enlightenment, and debate with them in the best possible manner. Your Lord knows best who has strayed from His path, and He knows best who are the guided ones.
16:126 And if you punish, you shall inflict an equivalent punishment. But if you resort to patience (instead of revenge), it would be better for the patient ones.
16:127 You shall resort to patience – and your patience is attainable only with GOD’s help. Do not grieve over them, and do not be annoyed by their schemes.
16:128 GOD is with those who lead a righteous life, and those who are charitable.
Rules of War*
2:190 You may fight in the cause of GOD against those who attack you, but do not aggress. GOD does not love the aggressors.
2:191 You may kill those who wage war against you, and you may evict them whence they evicted you. Oppression is worse than murder. Do not fight them at the Sacred Masjid, unless they attack you therein. If they attack you, you may kill them. This is the just retribution for those disbelievers. 2:192 If they refrain, then GOD is Forgiver, Most Merciful.
2:193 You may also fight them to eliminate oppression, and to worship GOD freely. If they refrain, you shall not aggress; aggression is permitted only against the aggressors.
Basic Law Regulating Relations With Unbelievers
60:8 GOD does not enjoin you from befriending those who do not fight you because of religion, and do not evict you from your homes. You may befriend them and be equitable towards them. GOD loves the equitable.
60:9 GOD enjoins you only from befriending those who fight you because of religion, evict you from your homes, and band together with others to banish you. You shall not befriend them. Those who befriend them are the transgressors.
An Unforgivable Offense
4:93 Anyone who kills a believer on purpose, his retribution is Hell, wherein he abides forever, GOD is angry with him, and condemns him, and has prepared for him a terrible retribution.