"What does the Bible mean that we are not to judge others?"

This is an issue that has confused many people. On one hand, we are commanded by the Lord Jesus, “Do not judge, or you too will be judged” (Matthew 7:1). On the other hand, the Bible also exhorts us to beware of evildoers and false prophets and to avoid those who practice all kinds of evil. How are we to discern who these people are if we do not make some kind of judgment about them?

Sixth Commandment, "Thou shalt not kill". In our language the word "kill" simply means to take a life. The word God used for "kill" is much more discriminate as it means the deliberate act of murder - taking a human life without justification.

So if you are going to use the Bible now he was an evildoer and his practice of evil was by killing his family and he broke the Sixth Commandment.