The Messenger of Allah ﷺ said, "The heart is called the heart only because of how it turns about. The heart is like a feather hanging at the base of a tree, which the wind keeps flipping over from one side to the other."
قال وقال رسول الله ﷺ إنما سمي القلب من تقلبه إنما مثل القلب كمثل ريشة معلقة في أصل شجرة يقلبها الريح ظهرا لبطن
No references are available.
Its isnad is sahih, mentioned previously at 19014.