The breadth of Jesus' message is that if we found ourselves in any position that we thought killing would be OK - The correct response would be to actually love that person instead.
The life of the human body is irrelevant to the eternal life of the spirit.
** We are to Kill the spirit of evil in that person with love. **
(Don't forget, evil spirits are transferable and contagious.)
This doesn't mean that if they will continue to be a danger to others that they can't be locked up but to kill is the enemy winning.
To love is God winning.
A thief comes to steal, kill, and destroy. But I came to give
life—life that is full and good.
-John 10:10
"Moses gave you the law, right? But you don’t obey that law. If you
do, then why are you trying to kill me?” -Jesus - John 7:18
Matthew 10:28 (NET)
Do not be afraid of those who kill the body but
cannot kill the soul. Instead, fear the one who is able to destroy
both soul and body in hell.
The life of the human body is irrelevant to the eternal life of the spirit.
The other answers here are earthly perspectives.
Which would you rather be - enter the next world from natural causes a few years after killing your enemy or enter the next world killed by your enemy but without murder on your hands ??
Jesus died for His enemies. We are suppose to be little Christs.
Luke 9:55: http://www.biblestudytools.com/commentaries/gills-exposition-of-the-bible/luke-9-55.html
But he turned and rebuked them.
He turned himself about to them, and
looking upon them with a stern countenance, sharply reproved them for
their intemperate zeal, their passion of wrath, and anger, and desire
of revenge:
and said, ye know not what manner of spirit ye are of;
or do not
consider that this is not the true spirit of zeal, but of anger and
revenge; and is not agreeable to the spirit of the meek and humble
followers of Christ, or to the Spirit of God, and those gifts of his
bestowed on them, nor to the spirit of the Gospel dispensation: so
good men, for want of attention, may not know sometimes from what
spirit they act; taking that for a good one, which is a very bad one;
being covered with specious pretenses of love and zeal, and the
examples of former saints; not observing the difference of persons;
times, and things.
-
Love Your Enemies
27 “But I say to you people who are listening to me, love your
enemies. Do good to those who hate you. 28 Ask God to bless the people
who ask for bad things to happen to you. Pray for the people who are
mean to you. 29 If someone hits you on the side of your face, let them
hit the other side too. If someone takes your coat, don’t stop them
from taking your shirt too. 30 Give to everyone who asks you for
something. When someone takes something that is yours, don’t ask for
it back. 31 Do for others what you want them to do for you.
32 “If you love only those who love you, should you get any special
praise for doing that? No, even sinners love those who love them! 33
If you do good only to those who do good to you, should you get any
special praise for doing that? No, even sinners do that! 34 If you
lend things to people, always expecting to get something back, should
you get any special praise for that? No, even sinners lend to other
sinners so that they can get back the same amount!
35 “I’m telling you to love your enemies and do good to them. Lend to
people without expecting to get anything back. If you do this, you
will have a great reward. You will be children of the Most High God.
Yes, because God is good even to the people who are full of sin and
not thankful. 36 Give love and mercy the same as your Father gives
love and mercy.
Luke 9
23 Jesus continued to say to all of them, “Any of you who want to be
my follower must stop thinking about yourself and what you want. You
must be willing to carry the cross that is given to you every day for
following me. 24 Any of you who try to save the life you have will
lose it. But you who give up your life for me will save it. 25 It is
worth nothing for you to have the whole world if you yourself are
destroyed or lost. 26 Don’t be ashamed of me and my teaching. If that
happens, I[a] will be ashamed of you when I come with my divine
greatness and that of the Father and the holy angels. 27 Believe me
when I say that some of you people standing here will see God’s
kingdom before you die.”
Sorry but this commandment means exactly what it says.
God and Jesus are telling us not to take life in any context or situation.
God is all powerful and perfect - if he want's someone gone He can do it himself, He can wipe out an entire continent or the world with a flood if needed. I don't think I need a reference for that one.
With that said, why would we think we need to kill any one in any context, innocent, non-innocent, enemy, friend, slay in war, etc.
That would be taking the matter into our own hands and not trusting God.
God can change a killing situation in a second:
"For the word of God is quick, and powerful, and sharper than any two
edged sword, piercing even to the dividing asunder of soul and spirit,
and of the joints and marrow, and is a discerner of the thoughts and
intents of the heart." (Hebrews 4:12 KJV).
God is also trying to protect us from being killed:
Then said Jesus unto him, Put up again thy sword into his place: for
all they that take the sword shall perish with the sword (Matthew
26:52, King James Version)
The commandment is also reiterated from Jesus' mouth.
Matthew 19: 16-18
16 A man came to Jesus and asked, “Teacher, what good thing must I do
to have eternal life?”
17 Jesus answered, “Why do you ask me about what is good? Only God is
good. But if you want to have eternal life, obey the law’s commands.”
18 The man asked, “Which ones?”
Jesus answered, “‘You must not murder anyone, you must not commit
adultery, you must not steal, you must not tell lies about others, 19
you must respect your father and mother,’[e] and ‘love your
neighbor[f] the same as you love yourself.’[g]”
He says:
Exodus 20:13 (KJV) Thou shalt not kill.
Notice that there are no unless, or if this, or that...etc.
The Old Testament commands to fight wicked nations, but that does not apply in the New Testament. For example,
The Catholic Church teaches that the Law of Moses (the Old Law) is a
preparation for the Gospel, and as such no longer binding. The New Law
(the Law of Gospel) is a perfection of it, given through faith in
Christ.
And here is an example of a perfect part: Jesus specifically tells us at the Sermon on the mound we should not stand up for ourselves and that we should pray for such people. When Jesus returns He will then take care of the wicked or will call us to help Him. It is very hard to accept. (Do I personally think I could do it in all situations, I do not know...but looking at Jesus the answer is there.)
We forget Jesus IS GOD - FROM GODS MOUTH: read carefully:
You have heard that it was said, 'An eye for an eye, and a tooth for a
tooth.' But I say to you, do not resist an evil person; but whoever
slaps you on your right cheek, turn the other to him also. If anyone
wants to sue you and take your shirt, let him have your coat also.
Whoever forces you to go one mile, go with him two. Give to him who
asks of you, and do not turn away from him who wants to borrow from
you. You have heard that it was said, 'You shall love your neighbor
and hate your enemy.' But I say to you, love your enemies and pray for
those who persecute you. (Matthew 5:39-44)
Doesn't leave much room for killing. Some say it is Jesus using a hyperbole but if He was he would have said so.
Even "violent white KKK Christians" are leaning more towards what Jesus was trying to say here:
"Odinism has lately gained in popularity among white supremacists who
believe that Jesus is too peaceful and too Jewish to worship, White
said. "It's hard to get a violent god out of Jesus."
As followers in Christ, we do not belong to any country, we belong to our Lord. We are told to obey them but not if it contradicts the word of God.
So being a Christian and in the Military IN A POSITION OF KILLING is not really a Christian concept. There are may Christians who during WWII refused to carry a weapon and were pushed into medical care and other service positions.