Likutei Moharan 250:7/ליקוטי מוהר"ן ר״נ:ז׳

17. And this is the aspect of “Chizkiyahu wept a great deal” (Isaiah 38:3), which was said when he took sick. Specifically “wept a great deal,” for he infused the weeping with vision and Providence, which are the aspect of greatness/prayer, etc., as explained above.

2This is also what was said of David when he wept about his suffering: “until David [had wept] a great deal” (1 Samuel 20:41)—his weeping reached the aspect of Providence, the aspect of greatness, as explained above. This is because through Providence we are saved from all manner of suffering and afflictions, as explained above.