Allah the Exalted has said:
"Verily the Good shall drink of a Cup (of wine) mixed with Kafur. A fountain where the Devotees of God do drink, making it flow in unstinted abundance. They perform (their) vows, and they fear a Day whose evil lies far and wide. And, they feed, for the love of God, the indigent, the orphan and the captive. Saying, `We feed you for the sake of God alone; no reward do we desire from you, nor thanks.' `We only fear a Day of distressful Wrath from the side of our Lord.' But, God will deliver them from the evil of that day, and will shed over them a light of Beauty, and a (blissful) Joy. And, because they were patient and constant, He will reward them with a Garden and (garment of) silk. Reclining in the (Garden) on raised thrones, they will see there neither the sun's (excessive heat), nor, (the moon's) excessive cold. And, the shades of the (Garden) will come low over them, and the bunches (of fruit), there, will hang low in humility. And, amongst them will be passed round vessels of silver, and goblets of crystal; Crystal clear, made of silver. They will determine the measure thereof (according to their wishes). And, they will be given to drink there of a Cup (of wine) mixed with Zanjabil. A fountain there, called Salsabil.
And around about them will (serve) youths of perpetual (freshness): if thou seest them, thou wouldst think them scattered Pearls. And when thou lookest, It is there thou wilt see a Bliss and a Realm Magnificent. Upon them will be green garments of fine silk and heavy brocade, and they will be adorned with Bracelets of silver; and their Lord will give to them to drink of a Wine pure and Holy. Verily this is a Reward for you, and your Endeavor is accepted and recognized." (76: 5-22)
These verses were revealed after ‘Ali (as), Fatima az-Zahra (sa), Hasan (as), and Husayn (as) gave charity to needy people; this story is stated in the book Al-Kashaf by Zamakhshari; it goes as follows:
"Ibn Abbas said:
`Once Al-Hasan and Al-Husayn (as) were ill, the Messenger of Allah and a group went to visit them. The visitors suggested to Imam ‘Ali (as) to make a vow to Allah: if He were to relieve them, he would perform some good action. Therefore, Imam ‘Ali together with Fatima and their servant Fidhdha vowed to Allah that they would fast for three days if He would relieve Hasan and Husayn.'
'When Allah had relieved them, Imam ‘Ali (as) borrowed three (3) aswu (a cubic measure) of barley from a Jew known as Shimon. Fatima ground one (1) sa'a (singular of aswu) of the barley and baked five loaves of bread for her family's meal at sunset. As sunset approached, a needy man knocked on the door and said: Assalamu Alaikum, Family of Muhammad. I am a needy man from among the Muslims, feed me, may Allah feed you from the food of Paradise.' The holy family preferred the needy man over themselves and spent the night with nothing in their stomachs save water.'
'They fasted the second day, and again at sunset, when they were waiting for their food, an orphan asked them for help and they again preferred him over themselves. The third evening a captive (prisoner of war) asked them for help and they repeated their preference for the needy above themselves.'
'The following morning, Imam ‘Ali (as) took Al-Hasan and Al-Husayn to the Messenger of Allah (S) who said the following when he saw them shaking like little chicks from hunger:
"The Prophet (S) said: It displeases us to see you in this condition.'
Then he went with them, for he wanted to see Fatima. When they arrived, Fatima (sa) was in the Mehrab (prayer place), and her condition was such that it further displeased the Prophet (S). At this time, Gabriel descended and said:
`Take this chapter Muhammad, - Allah surely congratulates you for having this family. "
It is worthy to state that the Good ones mentioned here are ‘Ali (as), Fatima az-Zahra (sa), Hasan (as), and Husayn (as); who deserve Paradise because of their act of feeding the needy, the orphan, and the captive.
Another point to keep in mind here is that despite the detailed description of Paradise given in the verses, Allah, the Exalted, does not mention the “huris”. This understood to be in honor and exaltation of Fatima az-Zahra (sa) the wife of Imam ‘Ali (as), and the mother of Hasan (as) and Husayn (as).