Musannaf Ibn Abi Shayba 37:510

Waki’ narrated to us, from Sufyan, from al-Harith ibn Hasirah, from Zayd ibn Wahb, who said: It was said to Hudhayfah, "What are the pauses of the tribulation (fitnah) and what are its uprisings?" He said, "Its uprisings are the drawing of the sword, and its pauses are the sheathing of it."