It is narrated from Sayyiduna Ka'b bin Malik (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: The soul of a Muslim resides in the form of birds on the trees of Paradise until the Day of Resurrection, when Allah will return it to its body.
Hadith Referenceمسند احمد / مسند المكيين / 15787
Hadith Gradingحکم دارالسلام:حديث صحيح، خ: 2757، م: 2769، وهذا إسناد ضعيف، عامر بن صالح ضعيف