Silsilat al-Ahadith al-Sahihah

Sayyiduna Ka‘b bin Malik (may Allah be pleased with him) says: When the time of Ka‘b’s death approached, Umm Mubashshir bint Bara bin Ma‘rur came to him and said: O ‘Abdur Rahman! If you meet my son, convey my greetings to him. He said: Umm Mubashshir! May Allah forgive you, we will be preoccupied and will not be able to do such a thing. She said: O ‘Abdur Rahman! Be alert! Did you not hear the Messenger of Allah (peace and blessings be upon him) say: “Indeed, the souls of the believers are inside green birds, they eat from the trees of Paradise.” He said: Why not (I have heard it). She said: That is exactly what I am saying.