"You have heard that it was said to the people long ago, 'Do not murder, and anyone who murders will be subject to judgment.' 

                                                                                Matthew 5:21

Here regarding sinning, Jesus teaches us not to hate.  

As a believer in God, we should follow the Ten Commandments. For example, “You shall not commit adultery” should be governed in the mind; “You shall not murder” must begin with taming the anger.

Hatred is the root of murder. When hatred accumulates to a certain degree, murder will happen. 

 Later on, the Son of Man was resented and envied, and eventually targeted for death by the priests, Pharisees, and scriptural scholars. They didn’t start with a plan to kill Jesus, but when envy and hatred took over, it ended with a murder.  Therefore Jesus teaches us not to hate, because constant hatred may lead to the thought of killing.

The Ten Commandments in the Old Testament doesn’t say “Don’t hate”, but Jesus in the New Testament tells us not to hate others. The old testament only says not to kill, steal, commit adultery, or lie, but all of these must be restrained from the mind in order to transform oneself. 

This part of Jesus’s teaching is very important.