852. hadíth
"اَلْأَرْوَاحُ جُنُودٌ مُجَنَّدَةٌ فَمَا تَعَارَفَ مِنْهَا اِئْتَلَفَ وَ مَا تَنَاكَرَ مِنْهَا اِخْتَلَفَ".
The Prophet (saws) said; "The souls are like recruited soldiers; those that recognize one another will find harmony, and those that do not will be in discord." (regarding spiritual affinity between individuals)