Kitāb al-Ghayba

Hadith 678
occultation
412- الفضل بن شاذان، عن الحسين بن يزيد الصحاف عن منذر الجواز عن أبي عبد الله عليه السلام قال: كذب الموقتون، ما وقتنا فيما مضى، ولا نوقت فيما يستقبل.
H 412 - Fadhl bin Shazan has narrated from Husain bin Yazid Sahaf from Mudhir Jawwaz from Imam Ja’far Sadiq (a.s) that he said: “One who fixes (predicts) the time of the reappearance, has lied. Neither have we fixed a time for it in the past nor would we do so in future.”
Source: Shaykh Muḥammad b. al-Ḥasan al-Ṭūsī