Usul al-Kafi
Book 4:
The Book of Divine Proof

Chapter 84
Recognition of the Imam

460. 2. Imam Jafar as-Sadiq (p) was asked to comment on the verse: One day we shall call together all human beings with their (respective) Imams ... (Q, 17:71).
The Imam (p): Recognize your Imam (p). An early recognition or a delayed recognition will not make any difference. Anyone who recognizes his Imam (p) and dies, before he could serve Hujjat, will be like the one who is a soldier in the army of the Imam (p).

461. 3. Imam Jafar as-Sadiq (p) was asked: When the Hujjat will appear (and will establish the kingdom of God over the world)?
The Imam (p): Are you also among those people who are impatient for worldly gains? One who recognizes his Imam (p) finds pleasure in waiting for the Imam’s (p) reappearance.
462. 5. Imam Muhammad al-Baqir (p): One who dies without recognizing his Imam (p) dies in ignorance, and one who dies having recognized his Imam (p), regardless of the delay in recognition, is like the one who is with the Imam (p) in his pavilion.
463. 7. Imam Jafar as-Sadiq (p) urged the people to recognize their Imam (p) and that any delay in recognition will be immaterial. Referring to the verse: One day we shall call together all human beings with their (respective) Imams (p) (Q, 17:71), the Imam (p) said: One who has recognized his Imam (p) is like the one who will be (under his command) in his pavilion.