This is a reference to Jaʿfar al-Ṣādiq's avoidance of participating in any political activities during the anti-Umayyad revolution of his time, despite the expectations of some of his followers and admirers that he would provide leadership. Hossein Modarressi cites this reference in his discussion of some of the features of al-Ṣādiq's political stance.
This source is part of the Online Companion to Hossein Modarressi, Text and Interpretation: Imam Jaʿfar al-Ṣādiq and His Legacy in Islamic Law (Harvard University Press, 2022).