הלכה אויף ירמיהו 5:3

He who does not mourn, in the manner the Sages have ordained, is considered a heartless person. But he should arouse himself from his sleep, examine his deeds with fear and anxiety, and repent and then, perhaps he may be spared from the sword of the angel of death. For it is said, "You have smitten them, but they were not greived,"⁶Jeremiah 5:3. which indicates that a person must awaken, examine [his deeds] and repent.