Lady Aisha (may Allah be pleased with her) says that the Messenger of Allah (peace and blessings be upon him) said: "Souls are like gathered armies; those who became acquainted with one another (in the realm of souls) feel affection for each other here (in the world), and those who remained unfamiliar with one another there are opposed to each other here."
Hadith Referenceمسند الشهاب / 274
Hadith Gradingمحدثین:إسناده صحيح
Hadith Takhrij«إسناده صحيح ، وأخرجه البخاري : 3336، وابويعلي : 4381،- ومسلم : 2638، من حديث أبى هريرة»