Spitefulness is the traces remaining of others unpleasant actions and words, in the inner self, of the one was spited. For indeed, the mind decides the traces of others unpleasant deeds to remain as it decides for the traces of others pleasant deeds to remain.
Abdullah ibn Kab ibn Malik narrated that he heard Kab ibn Malik's story when he did not join the Messenger of Allah (saw) in Tabuk and the story of the revelation of the acceptance of his repentance. He said:
"I entered the Masjid, while the people were gathered around the Messenger of Allah (saw), so Talhah ibn Ubaydillah ran to me, shook my hand and congratulated me. By Allah! He was the only man of the immigrants who did that." He said, "So Kab never forgot Talhah for this." [Bukhari and Muslim]
So if it is proven that good deeds and favors are not forgotten, so too are bad deeds not forgotten. Nevertheless it is preferred to try and remove the traces of any ugly deed from the heart. The cure of spitefulness is forgiveness and remission.
There are two stages of forgiveness: First is to know the reward of someone who forgives, second to thank the One Who made one be in the position of the forgiver and the other in the position of one who errs. The perfection of forgiveness can be reached through being content and this happens by removing all that is in the heart against the other person.
There is a more precise cure than this that I have mentioned and it is that a person knows that he was harmed because of a sin that he committed, or to wipe away a sin, or to raise his rank, or to test his patience. Yet a more precise cure is to understand that everything that happens to him is from the One who predestines.
The Virtue of the Mind
Dispraise of Hawa (desires)
The Difference Between the Perspective of Mind and the Perspective of Hawa
Averting Passionate Love (Ishq)
Averting Gluttony (Sharah)
Refusing to take a Position of Authority in this world
Prohibition on Squandering
Elucidation on the Amount of Earnings and Expenditure
Dispraise of Lying
Averting Riya (Insincerity and Pretentiousness)
Averting Excessive Thinking
Averting Excessive Sadness
Averting Ghamm (Grief) and Hamm (Worry)
Averting Excessive Fear and Cautiousness of Death
Averting Excessive Happiness
Identifying One's Flaws
Motivating a Low Endeavor
Disciplining and Handling Family and Slaves
Consorting with People
Flawlessness of Character