God commanded people to kill in the Old testament, does he still command people to kill today? As the title states. God commanded people to kill in the Old testament, does he still command people to kill today?

There are people who claim God commanded them to Kill. Is this legit? Or is there clear evidence in the Bible that goes against this?

Examples of God commanding people to Kill in the Old Testament:


  1 Samuel 15:3 Now go and smite Amalek, and utterly destroy all that
  they have, and spare them not; but slay both man and woman, infant and
  suckling, ox and sheep, camel and ass.
  
  NUMBERS 21:3 The Lord gave the Canaanites over to Israel, who
  "completely destroyed them and their towns."
  
  NUMBERS 31:17-18 God commanded Moses to kill all of the male Midianite
  children and "kill every woman who has slept with a man, but save for
  yourselves every girl who has never slept with a man." The virgins
  were presumably raped. (NOTE: How could the soldiers know which women
  were virgins?)


There are lots of sources out there:

http://www.evilbible.com/Murder.htm
http://rationalwiki.org/wiki/Examples_of_God_personally_killing_people
http://www.thethinkingatheist.com/page/bible-atrocities

I understand that most of this makes sense in context of the Old Testament. But what about people who kill today and say God commanded them to? Is this legit? Can we deny their claim?
While God did command nations to kill, it's important to remember that he never commanded individuals to kill devoid of their representing a nation.  

So no, I don't think you could say that it is legit for any single individual to claim that God commanded them to kill.  On the contrary, one of the ten commandments is, "You shall not murder." (Exodus 20:13).  The word that God uses for murder is different than the word that is used to mean "kill" when it is carried out in war.  

So to answer your question, yes.  You can deny their claim.  They were not told by God to murder.  

You can read more about the words used here.