Haafiz ibnul Hajar ‘Asqalaani (rahimahullah) has mentioned that Hazrat Bilaal (radhiyallahu ‘anhu) was the treasurer of Nabi (sallallahu ‘alaihi wasallam).
Hazrat ‘Abdullah Al-Hawzani (rahimahullah) mentions that he once met Hazrat Bilaal (radhiyallahu ‘anhu) in Halab (a city in Shaam). On meeting Hazrat Bilaal (radhiyallahu ‘anhu), he asked him, “O Bilaal (radhiyallahu ‘anhu)! Tell me of the manner in which Nabi (sallallahu ‘alaihi wasallam) would spend wealth for the cause of deen.” Hazrat Bilaal (radhiyallahu ‘anhu) replied:
From the time Allah Ta‘ala deputed him as a Nabi until he left this world, the wealth he possessed was entrusted to me. Whenever a Muslim would come to him and he would notice that he did not have sufficient clothing, he would instruct me to provide clothing for him. I would therefore take a loan through which I would purchase a shawl and whatever else was needed after which I would clothe and feed that person. This continued until, one day, a disbeliever approached me and said, “O Bilaal (radhiyallahu ‘anhu)! I possess plentiful wealth so don’t go to anybody else when you need a loan.” Accordingly, I commenced going to him for loans and ceased taking loans from other people.
One day, when I had performed wudhu and was now standing, about to call out the azaan for salaah, I saw the same disbeliever nearby amongst a group of traders. When he spotted me, he called out, “O Abyssinian!” and began speaking to me very rudely and harshly. He asked me, “Do you know how long it is until the end of the month?” I replied, “The end of the month is close.” He said, “There are only four nights left! When the month is over, I am going to take you as my slave in exchange of the money you owe me. I have not been loaning you wealth due to you or your companion’s honor. I only gave you loans so that you will become my slave and I will make you graze the goats once again.” When I heard these words, I was alarmed and taken by surprise. Nevertheless, I called out the azaan and we performed Esha salaah.
When Nabi (sallallahu ‘alaihi wasallam) returned home after the salaah, I went to him and sought permission to enter and speak to him. When he granted me permission, I entered and said, “O Rasul of Allah (sallallahu ‘alaihi wasallam)! May my father and mother be sacrificed for you! I had mentioned to you that I am taking loans from a certain disbeliever. That same disbeliever has now threatened to take me as his slave if I do not pay him by the end of the month. Neither you nor I have the means to pay him and he wishes to disgrace me. Permit me to flee to some other locality which has accepted Islam where I will remain until Allah Ta‘ala provides you with the means to pay the money I owe.” I then left and proceeded home. On reaching home, I collected my sword, bag, spear and sandals and left them at my head side after which I lay down, facing the horizon. Such was my state of worry that I was initially unable to sleep. Whenever I fell asleep, I would instantly awake with a shock. I eventually managed to fall and remain asleep and only awoke when the rays of subh saadiq (first dawn) had spread horizontally across the sky.
I had just decided to set out and leave when a person came running to me calling, “O Bilaal (radhiyallahu ‘anhu)! Respond to the call of Rasulullah (sallallahu ‘alaihi wasallam)!” I immediately hastened towards Rasulullah (sallallahu ‘alaihi wasallam) and, on reaching him, saw four animals laden with goods nearby. Nabi (sallallahu ‘alaihi wasallam) addressed me saying, “Glad tidings! Allah Ta‘ala has created means for you to pay off your debt.” I praised Allah Ta‘ala on hearing this good news and Nabi (sallallahu ‘alaihi wasallam) asked, “Did you not pass by the four animals kneeling (nearby)?” I replied in the affirmative to which Rasulullah (sallallahu ‘alaihi wasallam) said, “Verily the camels together with their loads are yours.” When I looked, I saw that they were laden with fabrics and food which the leader of Fadak had gifted to Rasulullah (sallallahu ‘alaihi wasallam). Nabi (sallallahu ‘alaihi wasallam) said, “Take them with you and settle your debts.” I did as instructed, taking the camels and offloading the goods. I then tied the camels and went to call out the azaan for the Fajr salaah.
When we had completed performing the Fajr salaah, I made my way to Baqee‘ and inserted my fingers into my ears (to assist me to raise my voice) and called out at the top of my voice, “Whoever wishes to collect the money which Rasulullah (sallallahu ‘alaihi wasallam) owes him should present himself!” I continued to sell the goods and pay the debts as the creditors arrived, bartering in exchange of the monies owed, until every single debt had been settled and I even had one and a half or two ooqiyah to spare.
By this point, most of the day had already passed. I went to the musjid where I found Rasulullah (sallallahu ‘alaihi wasallam) sitting on his own. After I made salaam to him, he asked me what had happened. I replied, “Allah Ta‘ala has paid every debt of Rasulullah (sallallahu ‘alaihi wasallam) so that no debt remains.” He then asked me, “Is there any leftover wealth?” “Yes, two gold coins.” I replied. Nabi (sallallahu ‘alaihi wasallam) urged me saying, “See that you relieve me of them (by giving them in sadaqah)! I will not go to any of my wives until you have not relieved me of the two gold coins.” As nobody thereafter arrived to whom I could give the sadaqah, Nabi (sallallahu ‘alaihi wasallam) did not go to the homes of any of his wives and spent the entire night in the musjid.
Nabi (sallallahu ‘alaihi wasallam) remained in the musjid until the second day was now coming to an end. Only then did two travelers arrive who I took with me to feed and clothe. After we had performed the esha salaah, Nabi (sallallahu ‘alaihi wasallam) called me and asked me what had happened. I replied, “Allah Ta‘ala has relieved you of the wealth.” Nabi (sallallahu ‘alaihi wasallam) said “Allahu Akbar!” and praised Allah Ta‘ala out of gratitude as he had feared leaving this world while possessing the wealth. I then followed him as he went to the homes of all his respected wives, greeting them in turn, until he finally arrived at the home of the wife whose turn it was that night.”
Hazrat Bilaal (radhiyallahu ‘anhu) then said to Hazrat ‘Abdullah Al-Hawzani (rahimahullah), “This is the answer to your question, this is how Rasulullah (sallallahu ‘alaihi wasallam) would spend in the path of Allah Ta‘ala.”
(Hayaatus Sahaabah 2/267)