Thou shalt not hate thy brother in thine heart.... Thou shalt not avenge, nor bear any grudge against the children of thy people, but thou shalt love thy neighbour as thyself. Leviticus 19:17, 18. RC 70.1
The Saviour's words revealed to His hearers the fact that, while they were condemning others as transgressors, they were themselves equally guilty; for they were cherishing malice and hatred.... They cherished the most bitter hatred of their Roman oppressors and felt themselves at liberty to hate and despise all other peoples, and even their own countrymen who did not in all things conform to their ideas. In all this they were violating the law which declares, “Thou shalt not kill.” RC 70.2
The spirit of hate and revenge originated with Satan, and it led him to put to death the Son of God. Whoever cherishes malice or unkindness is cherishing the same spirit.... In the revengeful thought the evil deed lies enfolded, as the plant in the seed.... In the gift of His Son for our redemption, God has shown how high a value He places upon every human soul, and He gives to no man liberty to speak contemptuously of another. We shall see faults and weaknesses in those about us, but God claims every soul as His property—His by creation, and doubly His as purchased by the precious blood of Christ. All were created in His image, and even the most degraded are to be treated with respect and tenderness. God will hold us accountable for even a word spoken in contempt of one soul for whom Christ laid down His life.... RC 70.3
Jesus says that whoever shall condemn his brother as an apostate or a despiser of God shows that he himself is worthy of the same condemnation. RC 70.4
Christ Himself, when contending with Satan about the body of Moses, “durst not bring against him a railing accusation” (Jude 9). Had He done this, He would have placed Himself on Satan's ground, for accusation is the weapon of the evil one. He is called in Scripture, “the accuser of our brethren” (Revelation 12:10). Jesus would employ none of Satan's weapons. He met him with the words, “the Lord rebuke thee” (Jude 9). RC 70.5
His example is for us. When we are brought in conflict with the enemies of Christ, we should say nothing in a spirit of retaliation or that would bear even the appearance of a railing accusation. He who stands as a mouthpiece for God should not utter words which even the Majesty of heaven would not use when contending with Satan. We are to leave with God the work of judging and condemning.—Thoughts From the Mount of Blessing, 55-58. RC 70.6