The old testament
13 You shall not murder. Exodus 20:13, NET©
The sixth commandment is self-explanatory, you should not murder. In the old testament, there was death penalty and killing in war did not count as murder. That means there was a difference between killing and murdering. When innocent people were killed it counted as murder.
In the new testament
In the new testament, the commandment has been sharpened significantly. It’s not just about killing people physically but also mentally and emotionally.
15 Whosoever hates his brother is a murderer: and you know that no murderer has eternal life abiding in him. 1 John 3:15, KJV
Everything we do is motivated from our hearts. We say nothing and do nothing without having our hearts at it. The motive behind all murder is hatred. Hate is the root of murder.
Therefore, the one who hates his neighbor is a murderer, and the person who lives in hatred can not inherit eternal life. Hate and eternal life are not compatible.
Hate is murder – Matthew 5:21-22, NET©
21 You have heard that it was said to an older generation, “Do not murder,” and whoever murders will be subjected to judgment.
22 But I say to you that anyone who is angry with a brother will be subjected to judgment. And whoever insults a brother will be brought before the council, and whoever says “Fool” will be sent to fiery hell.
To live in anger towards other people and to hold on to unforgiveness is murder in the eyes of God.
Are you a murderer?
If you live in anger, hate, or hold on to unforgiveness, then you have sinned. The bible is clear, the one who does so is a murderer, and no murderer can have eternal life.
If you have committed this sin, then you must repent of your sin, and ask God for forgiveness. Forgive whoever you have not forgiven and receive Jesus as Lord.