A man complained to ‘Abdullah bin Mubaarak (rahimahullah) of a boil on his knee since seven years. He said: “I have tried different treatments and consulted many doctors but nothing has helped.” ‘Abdullah bin Mubaarak (rahimahullah) replied: “Dig a well in a place where people are in need of water. I hope that as soon as water gushes out from there, the blood will stop oozing from your wound.” The man did so and was cured. (Shu‘abul Imaan #3109)
Lesson: While all types of sadaqah are effective in removing calamities and attracting the mercy of Allah Ta‘ala, arranging water for those who are in need of it is one of the greatest forms of charity. Rasulullah (sallallahu ‘alaihi wasallam) even advised doing this as a form of thawaab jaariyah for the deceased.