If you knew what was in store for you with Allah, the Exalted, you would love to be increased in poverty and need
Authentic hadithعن فضالة بن عبيد رضي الله عنه : أن رسول الله صلى الله عليه وسلم كان إذا صلى بالناس يَخِرُّ رجال من قامتهم في الصلاة من الخَصَاصَة -وهم أصحاب الصُّفة- حتى يقول الأعراب: هؤلاء مجانين. فإذا صلى رسول الله صلى الله عليه وسلم انصرف إليهم، فقال: «لو تعلمون ما لكم عند الله تعالى ، لأحببتم أن تزدادوا فاقة وحاجة».
Fudālah ibn ‘Ubayd (may Allah be pleased with him) reported that when the Messenger of Allah (may Allah’s peace and blessings be upon him) led the people in prayer, some men would collapse while praying from hunger — Those were the people of the Suffah — until the Bedouins would say: "These people are mad." So when the Messenger of Allah (may Allah’s peace and blessings upon him) finished the prayer, he would turn to them and say: "If you knew what was in store for you with Allah, the Exalted, you would love to be increased in poverty and need."
Explanation
This Hadīth mentions that there were men who would collapse while standing in prayer out of hunger and weakness. These belonged to the people of the Suffah, i.e. the ascetic Companions who were destitute and homeless. They were more or less seventy men who lived at the back of the Prophet’s Mosque as they had no homes, no money, and no children. The desert people would think that they were insane when they saw them collapsing in prayer. So the Prophet (may Allah's peace and blessings be upon him) said to the people of the Suffah: "If you knew what was in store for you with Allah of good things, you would love to be in more poverty and need."
Source · Narrated by At-Termedhy
From the Hadith Encyclopedia (hadeethenc.com).