Hazrat Abulfadhl Al-Abbas’s loyalty was most clearly manifested when he went to the Euphrates River but abstained from drinking water. The well-known narration of the event, which is widely related to by the people, is that Imam Hussain (as) sent Hazrat Abulfadhl to fetch water. However, what I have read in authentic versions of the narration—like those of “Irshad” by Mufid and “Lohoof” by Ibn Tawous—is slightly different from the common narration, probably highlighting the significance of the event. In these authentic books it has been narrated that in the last moments, rather in the last hour, while thirst had compelled the little children so much–little girls and others in the camps–that Imam Hussain (as) and Abulfadhl (as) took it upon themselves and left together to fetch water. Hazrat Abulfadhl did not go alone, in other words; Imam Hussain (as) accompanied Abulfadhl towards the Euphrates River—a branch of the Euphrates which flowed through that region—in hopes of obtaining water for the camp site.
These two courageous and strong brothers fought while backing each other on the battle field. Imam Hussain (as) was about sixty years old, but he was among famous unique men in terms of his power and courage. His brother Abulfadhl al-Abbas was in his 30’s with all these outstanding features known to everyone. These two brothers would fight side by side, and back to back, in the midst of the enemy’s army, moving into the waves of enemy lines, breaking them. They did so in order to reach to the Euphrates in hopes they could get some water. It was in the midst of this challenging battle that Imam Hussain realized, suddenly, that the enemy had created a gap between him and his brother Abulfadhl Al-Abbas. It was also in the midst of those tough moments that Abulfadhl got closer to water and reached the Euphrates. As it has been narrated, he filled the water pouch to take it back to the camp. Anyone would agree he had the right to drink a fistful of water to sooth his own thirst, but he demonstrated his loyalty in that moment.
When Abulfadhl Al-Abbas was filling his palms with water, when he looked at the water, he remembered Imam Hussain’s lips, dry from thirst; maybe he remembered the little girls and other children screaming out for thirst. Maybe he remembered Ali Asghar crying out for thirst and he could not allow himself to drink water. He poured the fresh water onto his hands, it seeped out and back into the river before he left. It was when he was leaving the river that the enemy targeted him, and all those horrible events unraveled. Suddenly Imam Hussain (as) heard his brother from the midst of the enemy’s army calling out to him: “O’ Brother! Help your brother!”
Ayatollah Khamenei, April 14, 2000