In the Sermon on the Mount Jesus said, "Judge not, that you be not judged. For with what judgment you judge, you will be judged; and with the measure you use, it will be measured back to you” (Matthew 7:1-2).

This statement does not mean we are not to judge right or wrong, or good or evil. Jesus is pointing out God will judge us according to how we judge others: “And why do you look at the speck in your brother's eye, but do not consider the plank in your own eye? Or how can you say to your brother, 'Let me remove the speck from your eye’; and look, a plank is in your own eye? Hypocrite! First remove the plank from your own eye, and then you will see clearly to remove the speck from your brother's eye” (Matthew 7:3-5). Before we point out somebody else’s fault we need to humbly examine our own behavior according to God’s standards.

It is important to read Jesus’ statement concerning not judging in the context of the whole Sermon on the Mount recorded in Matthew 5, 6 and 7 before jumping to any conclusion Christ is doing away with standards of right and wrong when He tells us not to judge. For example, a comment Christ made before His pronouncement about judging is: "You have heard that it was said to those of old, 'You shall not commit adultery.' But I say to you that whoever looks at a woman to lust for her has already committed adultery with her in his heart” (Matthew 5:27-28).

The command against adultery is one of the Ten Commandments, and Jesus is pointing out standards of right and wrong, good and evil aren’t just actions, but are rooted in thoughts, emotions and motivations. He also expands on sixth commandment: "You have heard that it was said to those of old, 'You shall not murder ….But I say to you that whoever is angry with his brother without a cause shall be in danger of the judgment. And whoever says to his brother, 'Raca!' shall be in danger of the council. But whoever says, 'You fool!' shall be in danger of hell fire” (Matthew 5:21-22). ‘Raca’ means to consider a person as totally worthless.

Jesus judges adultery, lust and murder as sins, as well as ponting out that hatred is also a sin. Also, you and I do not have the right to determine if a person is worthless before God. That judgment is reserved for Jesus Christ.

Many people take Jesus’ statement to “judge not” to mean He doesn’t judge anyone, but in this same sermon Jesus warns about the coming judgment of God. And the standards of that judgment are God’s Commandments and Christ’s explanation of those commandments.

At the end of His sermon Jesus prophesies about His Second Coming: “Not everyone who says to Me, 'Lord, Lord,' shall enter the kingdom of heaven, but he who does the will of My Father in heaven. Many will say to Me in that day, 'Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?' And then I will declare to them, 'I never knew you; depart from Me, you who practice lawlessness!'” (Matthew 7:21-23). There is no stronger statement about judgment in the entire Bible.

When we put together the teachings of the Sermon on the Mount we get a clear picture of what Jesus is teaching about judging. In Matthew 5 through 7 He defines judging in three broad principles.

1. We are not to judge the actions of others based on our own standards, but on God’s standards of right and wrong. 

2. We should not declare another person as worthless to God.

3. We should adhere to Jesus’ instruction: “Hypocrite! First remove the plank from your own eye, and then you will see clearly to remove the speck from your brother's eye” (Matthew 7:5).

Notice Jesus used the word “hypocrite.” Hypocrisy means “acting a part.” The Greek word translated “hypocrite” in the New Testament was used to denote a stage actor. It was a custom for Greek and Roman actors to speak on stage while wearing masks. Jesus said that if we judge others without first judging ourselves we are hypocrites. We are wearing a Christian mask while not acting in a Christian way.