The Messenger of Allah ﷺ said, "When your brothers were struck down at Uhud, Allah placed their souls inside green birds that go down to the rivers of Paradise, eating of its fruits and taking shelter in lamps of gold suspended in the shade of the Throne. When they found how sweet their food, their drink, and their resting place were, they said, 'Who will carry word from us to our brothers that we are alive in Paradise and provided for, so that they do not lose interest in jihad or shrink back in battle?'Allah, the Exalted, said, 'I will convey your message to them.'"Then Allah revealed, "And do not think of those who have been killed in the way of Allah as dead" [Al Imran 3:169], to the end of the verse.
قال رسول الله ﷺ: لما أصيب إخوانكم بأحد جعل الله أرواحهم في جوف طير خضر ترد أنهار الجنة: تأكل من ثمارها وتأوي إلى قناديل من ذهب معلقة في ظل العرش، فلما وجدوا طيب مأكلهم ومشربهم ومقيلهم قالوا: من يبلغ إخواننا عنا أنا أحياء في الجنة نرزق لئلا يزهدوا في الجهاد، ولا ينكلوا عند الحرب؟ فقال الله تعالى: أنا أبلغهم عنكم. قال: فأنزل الله: {ولا تحسبن الذين قتلوا في سبيل الله أمواتا} [آل عمران: ١٦٩] إلى آخر الآية.
Abu Dawud (2520) narrated it from Uthman bin Abu Shayba, who said, "Abdullah bin Idris told us, from Muhammad bin Ishaq, from Ismail bin Umaya, from Abu Zubayr, from Saeed bin Jubayr, from Ibn Abbas," who said, and then he related it.Ahmad (2389) also narrated it through this same route, though there is disagreement among the manuscript copies as to whether it is a narration of Ahmad himself or of his son Abdullah. Hakim (2/88, 297) graded it sahih and said, "Sahih according to the criterion of Muslim."I say, the correct view is that it is hasan, because of Muhammad bin Ishaq and Abu Zubayr, both of whom practice tadlis. However, Muhammad bin Ishaq has explicitly stated that he heard it directly in another chain. This matter has already been discussed in the Sirah.