Assalamu A'laykum Wa Rahmatullahi Wa Barakatu, I have been wondering, how did our scholars like Sheikh Al Tusi (ra) know if person x is reliable or not?? And the same thing goes for the Sunni scholars, but I'd rather know how our scholars knew it first. I have been searching and searching, but I haven't found any luck, but that's probably because most of the stuff we have in our text is in Arabic, so its quite hard for a person like me who isn't that great at Arabic to understand what I am reading. Jazakullahu feekum