Punishment for those who don’t give Zakaat
There is a Hadith in Sahih Muslim:
Translation: Hadhrat Abu Dhar (May Allah be well pleased with him) says that I went to the Holy Prophet (Sallallahu alaihi wa sallam). He was sitting in the shadow of the Ka’aba. One seeing me, He said: By the Lord of the Ka’aba! They will be ruined. I sat down, but then stood up out of restlessness and said: O Prophet of Allah (Sallallahu alaihi wa sallam)! I would offer my mother and father in lieu of you! Who are they? The Holy Prophet (Sallallahu alaihi wa sallam) said: They are the mighty rich except those who spend in front, this side, that side and behind them and rich people like this are very rare. The person who has camels, cattle or goats and does not give Zakaat on them, on the Day of Judgment they will all come fatter than they had ever been and will strike that person with their horns and trample him (or her) with their horns. When the last animal will have finished trampling, the first will return to trample and until the reckoning of the people is over, this will go on happening. (Sahih Muslim, Hadith No. 2347)
In the exegesis of the aforementioned verse of the Holy Quran, Hadith have been mentioned like this Hadith of Musnad Imam Ahmad Bin Hambal:
Translation: Hadhrat Abu Hurairah (May Allah be well pleased with him) relates from the Holy Prophet (Sallallahu alaihi wa sallam) that when someone hoards wealth without giving Zakaat then on the Day of Judgment, that wealth will become a highly poisonous snake and there will be 2 dark points on its eyes. The snake will chase that person and that person will run from it. The snake will keep chasing it to the point that out of terror, that person will chew away his (or her) own fingers. (Musnad Imam Ahmad Bin Hambal, Hadith No. 9168)
More details of this warning are given in Sahih Bukhari:
Translation: It is narrated on the authority of Hadhrat Abu Hurairah (May Allah be well pleased with him), he says: The Holy Prophet (Sallallahu alaihi wa sallam) said: The person to whom Allah Most High has granted wealth and he (or she) didn’t give Zakaat of that wealth, then on the Day of Judgment, that wealth will be turned into a poisonous snake. There will be 2 dark points on its eyes. On the Day of Judgment, this snake will be put on the neck of the person like a yoke. It will bite both the jaws of that person and say: I am that wealth, that treasure of yours, on which you gave no Zakaat.
Then the Holy Prophet (Sallallahu alaihi wa sallam) recited this verse of the Holy Quran:
And those who are niggardly in giving away (from the wealth) which Allah has bestowed upon them out of His bounty must never consider this miserliness of any benefit for themselves; it is rather injurious to them. Soon on the Day of Resurrection this wealth, which they are niggardly about, will be put around (their necks) like a neck-fetter. To Allah belongs the heritage of the heavens and the earth (i.e. He will remain the Owner of the universe after your death in the same way as He owns it today). And Allah is Well Aware of all your deeds. Surah Al Imran (3:180) (Sahih Bukhari, Hadith No. 1403)
There is another Hadith in this regard:
Translation: It is narrated on the authority of Hadhrat Ahnaf bin Qais (May Allah be well pleased with him), he says: I came to Madina. I sat in a group in which there were chiefs of Quraish. Suddenly a person who was wearing coarse clothes came to them. He was dignified and his face was awe-inspiring. He stood near them and said: Give tidings of that stone to those who hoard wealth, which will be heated in the fire of hell and that stone will be placed on their nipples, which will then burst from the bones of the shoulder and it will be placed on the shoulder and it will burst out through the nipple and that stone will continue going through and through like that.
The narrator says: Those people lowered their heads and I didn’t see any one of them answering to Him. (Sahih Muslim, Hadith No. 2353)
[Excerpted from Zakaat - Rules and modern issues]