Al-Abbas ibn Ali was a whole world of virtues and merits.  His personality included each and every lofty characteristic.  It is however sufficient honor for him to be the son of Imam Ali Amir ul-Mu'minin (a); the model of human perfection.  Thus, al-Abbas inherited all elements of human perfection from his father and became, in the sight of Muslims, the epitome of virtue and high moral standards.  Let us now refer to some of these elements:

COURAGE
Since it denotes the soundness and perseverance of personality, courage is regarded as the highest characteristic of manhood.  Abu'l-Fadhl al-Abbas came into this characteristic from his father who was the ever most courageous.  Al-Abbas's maternal uncles, too, were characterized by this feature among all the Arabs.  He was a perfect world of valor; fear had never been on his mind during battles in which he participated with his father.(  al-Kibrit ul-Ahmar; 3/24). 
During the battle of at-Taff, al-Abbas gave the highest examples of heroism and courage.  In fact, that battle is seen as the greatest conflict in the history of Islam.  Facing the large gatherings of Yazid's army, al-Abbas manifested himself so bravely that he changed their courageous warriors into cowards and filled in the hearts of their troops with horror.  Losing any means to face this great hero, they went on using deceptive ways-they promised they would give him the general commandment of their army if he would leave the camp of his brother, but al-Abbas put them down and their promise was no more than a factor that increased his perseverance on his principles and persistence on defending his beliefs. 
Narrators have referred to the great casualties that Yazid's army suffered at the hands of al-Abbas ibn Ali who was, in the midst of that fighting, smiling.  He did fill the fields of that battle with the bodies of their victims, did paint their horses with their blood, and did plant horror and terror in their hearts.  His sword was a destroying thunderbolt that inflicted bereavement and fatality upon people of Kufa who were on the opposite party. 
The courage of al-Abbas has astonished poets and authors who have gone on describing it in nonesuch styles, and given the best examples of heroism all over history.  Since this courage was shown for defending the right and protecting the high values and principles of Islam, its significance has been increasing. 

FAITH
Faith was another major feature in the personality of al-Abbas.  He was brought up in the laps of the true faith, centers of God-fearing, and faculties of obedience to God.  His father; chief of the faithful and head of the pious, fed him with the essence of faith, and factuality of God's oneness.  Hence, al-Abbas grew up on the cognizant faith and the true pondering over the secrets of creation.  This giant, nonesuch faith interacted in the mentality of al-Abbas to change him into one of the great individuals of faith, piety, and sincerity.  Out of his faith, al-Abbas offered his brothers, sons, and himself as pure sacrifices for the sake of God. 
Bravely, al-Abbas fought for defending the religion of God and protecting the principles of Islam that were exposed to eradicative dangers during the reigns of the Umayyad ancestry.  He aimed at nothing other than the satisfaction of God and the attainment of the eternal joy of the life to come. 

DISDAIN
Disdain and sense of honor painted the personality of al-Abbas so densely that he refused completely to live in humbleness under the shadows of the Umayyad rulers who usurped the wealth of God and treated people as slaves.  Thus, he pushed himself in the fields of fighting, following his brother who raised the slogan of honor and dignity and declared that death would be no more than pleasure, while to live with the wrongdoers would be only humility. 
During the battle of at-Taff, al-Abbas represented all the concepts of disdain and sense of honor when he rejected proudly the commandment of Yazid's army if he would leave the camp of his brother.  As a result, he pushed himself sincerely in the fields of the battle, felling the warriors and harvesting his enemies' heads-all for defending his freedom, religion, and dignity. 

PATIENCE
On the day of Ashura, al-Abbas had to encounter unspeakable crises.  Nevertheless, he did not show any item of intolerance or worry and did not utter any single word of resentment.  On the contrary, he provided the whole matter to his Lord the Most High and copied his brother, al-Hussein (a), whose patience was as heavy as unshakable mountains. 
Al-Abbas saw the companions of his brother melted by the sun on the dust of Karbala, heard the weeping of the children out of their thirst and heard the moaning of the harem who were mourning for their men, and saw the loneliness of his brother who were encircled by the meanest enemies, intending to kill him so as to 'win' the prize of the governor of Kufa.  In the midst of all these crises, al-Abbas submitted to his Lord completely without showing any weakness. 

LOYALTY
Loyalty is the noblest characteristic one can have.  Al-Abbas set a record in this field when he represented all features of loyalty distinguishably:

LOYALTY TO THE RELIGION
Al-Abbas was the most faithful and the best defender of his religion.  When Islam had to encounter the eradicative danger of the Umayyad band who renounced Islam completely and declared war against it, al-Abbas dedicated himself to fighting on all fronts for defending his religion and raising the word of God on earth.  For sake of the principles of his religion, his hands were cut and he was martyred. 

LOYALTY TO THE NATION
As he noticed his nation sinking down under the gloomy nightmare of humility due to the absolute despotism of the Umayyad band who played in people's fates, al-Abbas understood that his mission was to proceed for saving them from this scathing fait accompli.  Along with his brother, family members, and those glorious companions, they raised the slogan of freedom and declared that holy jihad ceaselessly until they were martyred for so.  This in fact is the ever most elevated loyalty to the nation. 

LOYALTY TO THE HOMELAND
One of the Umayyad rulers, once, declared: "Iraq is no more than a garden possessed by Koreishites."  Hence, they regarded the Islamic homeland as a garden at their disposal.  On this account, poverty and misery were the two major characteristics of the Islamic homeland.  Besides, the righteous and the free people were subjected to humility.  Thus, al-Abbas, under the commandment of his brother, opposed this ruling regime and its authorities who, thanks to the self-sacrifices of al-Abbas and his party, collapsed.  This was the true loyalty to the Islamic homeland. 

LOYALTY TO HIS BROTHER
It is incumbent upon each Muslim to swear allegiance to the Imam who lives in his time.  Hence, al-Abbas gave the best example of being faithful to the allegiance to the Imam of his time-al-Hussein (a).  All over history, you cannot find an item of loyalty more exalted than that of al-Abbas to his brother and leader.  Hence, his loyalty has become the extremity that attracts every free, honest man. 

WILLPOWER
Willpower is one of the characteristics of the great ones whose deeds have always been successful, since it is impossible for the weak to achieve any social aim or any political work. 
Al-Abbas was full of determination; he joined the right camp and did not show any negligence or shortcoming.  On the stage of history, he has shown himself as being that glorious leader who deserves pride and immortality. 

MERCY AND KINDNESS
Al-Abbas enjoyed the highest standards of morality.  He was so kind and merciful with the underprivileged and the persecuted.  In Karbala, when the troops of Yazid occupied the banks of the Euphrates and deprived the other party of water, al-Abbas showed the most clear-cut signs of kindness and mercy when he saw his brother's children, as well as others, pale-faced and dry-lipped because of thirst.  Seeing this view, al-Abbas pushed himself towards the river and came back with water for those children.  On the tenth of Muharram, he also heard the children crying because of thirst; therefore, his kindness and feelings of mercy prompted him to sate their thirst.  He took the container and faced the enemies so bravely that he could take them away from the river.  As he was about to have a drink, he remembered the thirst of his brother and his children.  He therefore refused to drink before he would sate the thirst of those ones. 
Has anyone ever seen, heard, or known of such feelings of mercy and kindness at any person other than al-Abbas who climbed to the highest summits of glory because of the characteristics of his unique personality? 

CLEAR-SIGHTEDNESS
Clear-sightedness is originated from well-advisedness and intellectual genuineness.  It is attached to self-pureness and simple-heartedness, and enjoyed only by those who are free from control of passions. 
In the personality of al-Abbas, this characteristic was very clear.  It was the principal motive that incited him to support and follow Imam al-Hussein (a) to climb up to the summit of honor and glory.  Hence, his great personality has lasted forever as long as man is submitted to the human values whose summits and climaxes have been attained by al-Abbas, al-Abbas. 

STEADFAST FAITH
Imam as-Sadiq (a) testified to the unmatched character of his uncle al-Abbas when he attached the characteristic of steadfast faith to him.  This steadfast faith provoked al-Abbas to challenge the enemies in the fields of jihad and sacrifice himself for his religion. 

FIGHTING WITH IMAM AL-HUSSEIN
The testimony of jihad is the best proof on the perfection of personality.  Hence, Imam as-Sadiq (a) ascribes this great virtue to the personality of al-Abbas because of the latter's self-evident fighting for sake of his brother; Imam al-Hussein (a). 

ZIYARA OF IMAM AS-SADIQ
After he had visited the tombs of Imam al-Hussein, his household, and the virtuous companions, Imam as-Sadiq (a) ran to visit the tomb of his uncle al-Abbas.  He stood on that tomb and recited that famous Ziyara. 
Imam as-Sadiq (a) begins this Ziyara by seeking the greetings and salaams of God, His favorite angels, commissioned Prophets, righteous servants, and all martyrs and truthful ones to be on al-Abbas.  He then goes on testifying to his uncle of being submissive, believing, faithful, and sincere:

SUBMISSION
Al-Abbas submitted completely to his brother and leader, and followed him from top to bottom until he was martyred for his sake.  This unmatched submission was the result of al-Abbas's full acquaintance with the Imamate of al-Hussein (a) that is incumbent upon every Muslim.  Al-Abbas practiced all matters stemming from the divine commandment of the submission to the Immaculate Imams (a). 

BELIEF
Al-Abbas believed in God and gave full credence to his brother.  He surpassed all doubts in his belief of the equity of his issue.  He believed he was the right while his enemies were wrong. 

LOYALTY
Imam as-Sadiq (a) testified that his uncle al-Abbas accomplished his duties regarding the pledge of God and the loyalty to the Imam of his age utterly.  He supported the right party, stood steadfastly with his brother in the most intensive circumstances, and did not leave him until he was martyred although he lost his two hands.  Finally, al-Abbas was created to be faithful; therefore, his loyalty was a natural element of his personality and was also the fruit of the unparalleled loyalty of his parents. 

SINCERITY
Sincerity is another feature in the personality of al-Abbas to which Imam as-Sadiq (a) testified.  Al-Abbas was sincere in his fighting against the wrong and opposing the wrongdoers.  He played a great role in the jihad of his brother who took the leadership of struggling the wrong. 
In another paragraph of the Ziyara, Imam as-Sadiq (a) showed his great admiration for the great help and huge sacrifices that al-Abbas made for Imam al-Hussein.  He sacrificed himself, protected him with his dearest things, and tolerated steadfastly crises and hardships-all for sake of God.  God may reward him so remarkably on behalf of Prophet Mohammed, Imam Ali Amir ul-Mu'minin, Fatima az-Zahraa, al-Hasan, and al-Hussein (a). 
Imam as-Sadiq, in the same Ziyara, testified that his uncle al-Abbas followed the same line of the martyrs of Islam whose blood raised the word of God highly.  As he noticed the Umayyads' attempts to eradicate Islam and take people to the pre-Islamic customs and traditions, al-Abbas, under the leadership of his brother, revolted to keep the word of God high, to achieve victory to Islam, and to defeat the enemies and rivals. 
In the last paragraphs of the Ziyara, we notice the great rank of al-Abbas in the sight of Imam as-Sadiq (a) who testified to him that he did not show any shortcoming or retreat and did his best for sake of the religion.  Hence, the Imam beseeches to God to confer al-Abbas with eternal happiness, large place in Paradise, and companionship of the prophets, martyrs, and righteous ones. 

IMAM AL-MAHDI(A.S.)
The Great Reformist Imam al-Mahdi, God may hasten his return, said a great word about al-Abbas:
"Salaam be upon Abu'l-Fadl al-Abbas, son of Amir ul-Mu'minin.  He preferred his brother to himself, supplied himself with (opportunities of) today for (rewards of) tomorrow, sacrificed himself for his brother, protected him, hurried for fetching him water, and his two hands were cut (for such).  Allah curse his killers; Yazid ibn ar-Raqqad and Hukaim ibn at-Tuffail at-Taee…"
In the previous statement, Imam al-Mahdi praises al-Abbas for the noble characteristics that he enjoyed:
The Imam (a) commends al-Abbas for:
1.  Preferring his brother; the chief of the martyrs, to himself,
2.  Supplying himself with opportunities of this life for the life to come.  This is an indication to his piety, God-fearing, and support for the right and its people,
3.  Sacrificing his brothers, sons, and himself for Imam al-Hussein (a),
4.  Protecting his brother with his soul, and
5.  His efforts to fetch water to his brother and his harem when the other party encircled the Euphrates so as to prevent the party of Imam al-Hussein from having water even for their children and women.