The Book of the Believer · Hadith 176 (#Ḥadīth #6)
Chapter 8 | What Allah (azwj) has Forbidden a Believer to do Against a Fellow Believer
176 - وقال النبي صلى الله عليه وآله وسلم: من لا يعرف لأخيه مثل ما يعرف له فليس بأخيه.
176. The Prophet has said: One who does not care to know of his brother what he knows of him is not his brother.
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).