Allah Most High says, {And if you, O Prophet, see signs of betrayal by a people, respond by openly terminating your treaty with them. Surely Allah does not like those who betray.} (8:58)
He says too, {No Prophet could ever act dishonestly. If any person acts dishonestly, he shall, on the Day of Judgement, restore what he misappropriated, then shall every soul receive its due whatever it earned.} (2:161)

Abu Hurairah (radi Allahu anhu) heard the Prophet (peace be upon him) mentioning Ghulul, emphasizing its magnitude, and declaring that it was a grave sin, saying, “Do not commit Ghalul, for I would not like to see anyone amongst you on the day of Judgement, carrying over his neck a camel that will be grunting. Such a man will say, “O Allah’s Apostle! Intercede with Allah for me!” and I will say,” I cannot help you, for I conveyed Allahs’ message to you. Nor would I like to see a man carrying over his neck a horse that will be neighing. Such a man will be saying,” O Allahs’ Apostle! Intercede with Allah for me!” and I will reply,” I cannot help you, for I conveyed Allahs’ message to you”. Nor should I like to see a man carrying over his neck a sheep that will be bleating, or one carrying over his neck a crying soul, or one carrying over his neck clothes which will be fluttering, or one carrying over his neck gold and silver. Such men will be saying,’ O Allah’s Apostle! Intercede with Allah for us, and I will say,” I cannot help you, for I conveyed Allah’s message to you.” (Reported by Muslim)

Whosoever takes from these kinds of spoils before they are distributed among the fighters, or something from the Muslim’s common treasury without the Imam’s permission, or something from the Zakat fund which is assigned to the poor, will come on the Day of Judgement carrying it on his neck.

The Prophet (peace be upon him) said, “Render back (even) the thread and the needle, and shun Ghalul, for it puts man (who commits it) to shame on the Day of Judgement.” (Reported by Abu Dawud)

The Prophet (peace be upon him) appointed a man named “Ibn Al-Lutaibah for collecting the Zakah. When he returned, he said, “This (i.e., the Zakah) is for you, and this has been given to me as a present: whereupon, the Prophet (peace be upon him) ascended the pulpit and gave a sermon, saying, “By Allah, whoever takes something from the resources of the Zakat (unlawfully) will meet Allah carrying it on his neck on the Day of Resurrection.

Verily, I may know one of you who will meet Allah carrying on his neck a camel that will be grunting, or a cow that will be mooing, or a sheep that will be bleating. Then the Prophet (peace be upon him) raised his hands till we saw the whiteness of his armpits, and he said thrice, “O Allah! Have I not conveyed your message (to them)?” (Reported by A1-Bukhari and Muslim)

Abu Hurairah (radi Allahu anhu) narrated, “When we conquered Khaibar, we gained neither gold nor silver as booty, but we gained goods, food, and clothes. Then we departed with Allah’s apostle to the valley of ” Al-Qira”, and at that time Allah’s apostle had a slave of his called “Rifa’ah lbn Yazid, who had been presented to him by a man who had leprosy.

While the slave was dismounting the saddle of Allah’s apostle, an arrow (its thrower was unknown) came and hit him. The people said, ” Congratulations to him on his martyrdom”. Allah’s apostle (peace be upon him) said,” No, by him in whose hand is my soul, he had a sheet (of cloth) which he had taken (illegally) on the day of Khaibar from the booty before its distribution and has become a flame of fire burning him.” On hearing that, a man brought one or two leather straps of shoes to the Prophet and said, “These are the things I took (illegally)” “This is a strap, or these are two straps, of fire”, the Prophet (peace be upon him) said.” (Reported by Al-Bukhari)

Abdullah Ibn ‘ Amr (radi Allahu anhu) related, “There was a man who looked after the family and the belongings of the Prophet, who was called ‘Karkarah.” The man died, and Allah’s apostle (peace be upon him) said,” He is in the Hellfire. The people (peace be upon him) then went to look at him and found in his place a cloak he had stolen from the war booty.” (Reported by A1-Bukhari)

Zaid Ibn Khalid AI-Juhani (radi Allahu anhu) narrated, “A man has stolen something from the booty of Khaibar. As a result, the Prophet (peace be upon him) refused to observe the funeral prayer for him and said to his companions, ” Observe prayer for your fellowman, (and I would never observe it for him because he has stolen (from the booty obtained from war) in the way of Allah”

Zaid (radi Allahu anhu) added, “We, then, searched that man, luggage, and found therein some of the Jews’ pearls which were worth two drachmas.” (Reported by Abu Dawud)

Imam Ahmad related, “Allah’s apostle avoided prayer for none but the one who had stolen from the war booty and the one who had committed suicide. The Prophet (peace be upon him) said, “The gifts presented to official employees are a sort of Ghulul.” And there are numerous Prophetic traditions related to this point, and some of them are mentioned in the chapter of “Injustice” (Musnad of Imam Ahmad)

Injustice, generally speaking, may be classified into three categories:
a) To violently spoil one’s property.
b) To act tyrannically by unjustly killing, beating, or wounding people.
c) To aggressively insult, curse, slander, and ill-treat people.

The Prophet (peace be upon him), while being at “Mina,” gave a sermon that ended: “O People! Your belongings, and your honor are sacred to each other as sacred as this day, this month, and this city.” and: prayer is invalid without ablution, and charity is unlawful from Ghalul.” (Reported by AI-Bukhari)