The Messenger of Allah ﷺ said, "The souls of the martyrs reside in green birds that feed from the fruit of Paradise," or he said, "from the trees of Paradise."
أن رسول الله ﷺ قال: إن أرواح الشهداء في طير خضر تعلق من ثمرة الجنة أو شجر الجنة.
Tirmidhi (1641) narrated it from Ibn Abu Umar, and Ahmad (27166) narrated it as well, both of them from Sufyan (that is, Ibn Uyayna), from Amr bin Dinar, from Zuhri, from Ibn Kaab bin Malik (whose name was Abdul-Rahman), from his father, and he related it. Ahmad added, and it was read out to Sufyan, "A soul grazes on the fruit or the trees of Paradise." Tirmidhi said, "This is a hasan sahih hadith."I say, it is as he said, except that Humaydi (873) narrated it from Sufyan with the wording, "The soul of the believer is a green bird that grazes on the fruit of Paradise," with a story at its beginning.Likewise, more than one of the companions of Zuhri narrated it from Zuhri with the wording "the soul of the believer" or "the soul of the Muslim." Among them,Malik in Muwatta (566), and by his route Nasai (2073) and Ibn Majah (4271).Mamar, and his hadith is found with Ahmad (15776).And Layth bin Saad, and his hadith is found with Ibn Hibban (4657).They said, "The soul of the believer is but a bird that grazes among the trees of Paradise until Allah returns it to its body on the day He resurrects it," or words to that effect.Ibn Abdul-Barr said in Tamhid (11/58–59), "As for his saying 'the soul of the believer,' the soul here means the spirit, as shown by his ﷺ saying in the same hadith, 'until Allah returns it to its body on the Day of Resurrection.' The origin of this word, I mean 'nasamah,' is the human being himself, and the human being is called 'nasamah,' and Allah knows best, because the human being's life is by his spirit, so that when it departs from him he ceases to exist, or becomes as if he did not exist."His saying, "grazes among the trees of Paradise," is transmitted with a fatha on the lam, which is the more common reading, and it is also transmitted with a damma on the lam, the meaning being the same in both cases, namely eating and grazing. That is, it eats from the fruits of Paradise and grazes and roams freely among its trees.Some scholars, among them Ibn Hibban, held that what is meant by "the soul" here is specifically the soul of the martyr, and this is the view that Abu Umar adopted in Tamhid (11/64) and preferred.Others said that it is general, applying to every believing soul.