:The second reason is the necessity of knowing the Imam of each era
"It is a sign of faith"
Aban ibn Taghlib says: I asked Imam Sadiq: Is a person faithful if he knows all Imams except for the Imam of his own era? The Imam said: “No.” I asked again: Is he considered as a Muslim
The Imam answered: Yes
The Source: Kamal al-Din and Tamam Al-Nimeh
:The important lesson
"Every Muslim is not considered as a faithful one"