Kitāb al-Muʾmin

Hadith 119
brotherhoodrights
119 - وعن أبي عبد الله عليه السلام قال: أيما مؤمن سأله أخوه المؤمن حاجته وهو يقدر على قضائها فرده منها سلط الله عليه شجاعا 7 في قبره ينهش من أصابعه.
119. It has been reported that Abu 'Abd Allah (a.s) said: If any believer asks his fellow brother to help him and he refuses while he is able to do, Allah will impose on him a serpent in his grave to bite his fingers.
Source: Ḥusayn b. Saʿīd al-Ahwāzī