Al-Kāfi - Volume 1 > Setting-up a Time Limit for the Reappearance of the Twelfth Imam (a.s.) an Antipathetic Issue
Hadith #4

4ـ أَحْمَدُ بِإِسْنَادِهِ قَالَ قَالَ أَبَى الله إِلا أَنْ يُخَالِفَ وَقْتَ الْمُوَقِّتِينَ.

4. Ahmad has narrated through his chain of narrators from the Imam (a.s.) the following. “Allah disdains to make the people’s time set for it (reappearance of the one who will rise with Divine Authority) to come true.”