The example of a miser and a generous person is that of two men wearing two iron cloaks covering their breasts up to their collar bones
Authentic hadithعن أبي هريرة رضي الله عنه مرفوعاً: «مثل البخيل والمنفق، كمثل رجلين عليهما جُنتان من حديد من ثُدِيِّهما إلى تَرَاقِيهما، فأمَّا المنفق فلا ينفق إلا سَبَغت -أو وَفَرَت- على جلده حتى تخفي بنانه وتَعْفُو أثره، وأمَّا البخيل فلا يريد أن ينفق شيئاً إلا لزقت كل حلقة مكانها، فهو يوسعها فلا تتسع».
Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: “The example of a miser and a generous person is that of two men wearing two iron cloaks covering their breasts up to their collar bones. Whenever the generous person gives something away, his iron cloak expands until it becomes so wide that it will cover his fingertips and obliterate his traces. But whenever the miser thinks of spending, every ring of the iron cloak sticks to its place (against his body) and he tries to expand it, but it does not expand.”
Explanation
The Prophet (may Allah's peace and blessings be upon him) gave an example of the miser and the generous person. He described them as two men, each wearing an iron armor that covers him from the breast to the collar bone. Whenever the generous person spends in charity, his armor expands and increases in length until it drags behind him and covers his feet and footprints. As for the miser, he is like a man whose hand is tied to his neck, and whenever he tries to wear it (i.e. the armor), it gets more stuck to his neck and collar bone.
Source · Narrated by Bukhari & Muslim
From the Hadith Encyclopedia (hadeethenc.com).