If it were up to me murderers wouldn't be executed.I wouldn't kill them myself, and I wouldn't expect anyone else to. The night is always darkest before the dawn, and every person has capacity for change, remission or to find meaningful purpose.
'Have compassion for your enemies. Do good to those who hate you, speak no ill of those who curse you, wish-well for those who mistreat you'
Thou shalt not kill.
Do not condemn, that you are not condemned. For with what judgement you give, you will be judged; and with the measure you use, it will be measured back to you.
Have compassion for others as though they are you.
You have heard that it was said, 'Eye for eye, and tooth for tooth.' But I tell you, Do not resist an evil person. If someone strikes you on the right cheek, turn to him the other also.
Truly I say to you, whatever you did not do for even the least of (men), you did not do for me.
This is my instruction; that you have compassion for one another as I have for you. There is no greater compassion than this, to sacrifice one's life for another.
Murder is wrong. But murder is an action. And actions require intent, or a particular state of mind. Suppose that you go to town and you feel under a compulsion to give, even though you don't really want to give away your money. So you give the money and then feel regret that you did it, because you didn't really want to do it. The same applies to sins.
We often do things under compulsions. Sometimes those compulsions, or feelings that 'we must', last for weeks at a time. We brood on things. That is human nature.
And likewise is our desire for vengaence. We conform to the outward standards of society's brutal justic (death penalty) because inside, we think that it is right. We desire eye for eye, blood for blood, tooth for tooth.
But there is a big difference between lawfulness ad righteouness. The real cause of that brutal justice is not 'god'. God doesn't make us kill murderers. We have the choice to allow it or disallow it in society. And the pivotal point is this; it depends on how forgiving we are inside, as a society.