The Heidelberg Catechism, Question 105 asks, "What does God require in the sixth Commandment?"

The answer in part is: "That I do not revile, hate, insult or kill my neighbor either in thought, word, or gesture, much less in deed...."

The law is spiritual, the Apostle Paul said, which means that sins against the commandments originate in the spirit or in the heart of men. The ill will of the heart manifests itself in many ways, in thought, word, or deed. The outward manifestation of hatred, or inward murder, is described in four words:

Revile: Webster says this means "spread negative information about." It means to speak evil of a person, whether the information is true or false. When he was on the cross, the enemies of the Lord Jesus [Matt. 27:39] "reviled him" saying, "Thou who destroyest the temple and buildest it again in three days, save thyself." Paul said in 1Cor. 4:12 that it is the lot of the ministers to be reviled, but they must not revile again, for this is the example that the Lord Jesus set for us.

Hate: "33 Shouldest not thou also have had compassion on thy fellowservant, even as I had pity on thee? 34 And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him. 35 So likewise shall my heavenly Father do also unto you, if ye from your hearts forgive not every one his brother their trespasses." (Mt 18:33-35 AV) These are the words of Christ, and need no explanation.

Also: 43 Ye have heard that it hath been said, Thou shalt love thy neighbour, and hate thine enemy. 44 But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you; Matthew 5

Insult: Webster says that this means a "deliberately offensive act or word." The Bible forbids me to deliberately give offense to my neighbor. We are not to tempt others into sin, by hooking their anger, or triggering their sinfulness, for this is not love. We are to be gentle unto all men and patient.

Kill: This is obvious. We are not to shed the blood of our neighbor.

Reviling and insult are prime ingredients of contentiousness in a church. Because of the destructiveness of contentiousnes it is especially marked out for discipline in the constitution of the Reformed Church in the U.S. Webster defines contentiousness as "a disposition to fight." The Greek word implies quarrels among friends.