Musnad Ahmad 424:0

Narrated Al-Miqdad ibn Al-Aswad: I heard the Messenger of Allah (ﷺ) say: "The heart of the son of Adam is more prone to changing than a pot that is boiling over." I said: "O Messenger of Allah, if the heart of the son of Adam is more prone to changing than a pot that is boiling over, then what is the remedy?" He said: "The remedy is to hold fast to the Book of Allah and the Sunnah of His Prophet. For indeed, the heart of the son of Adam is more prone to changing than a pot that is boiling over."