Zakaah is another pillar of Islam which is compulsory on the one whom Allaah has blessed with money/fruits/crops/property or another thing that is subjected to zakaah and it reaches the nisaab (minimum threshold) and satisfies other conditions specified for it.
Allaah says (interpretation of the meaning):
“And those who hoard up gold and silver (Al‑Kanz: the money, the Zakaah of which has not been paid) and spend them not in the way of Allaah, announce unto them a painful torment…” [al-Tawbah 9:34-35]
The prophet (peace and blessings of Allaah be upon him) said, “Whoever is made wealthy by Allah and does not pay the Zakaah of his wealth, then on the Day of Resurrection his wealth will be made like a bald headed poisonous male snake with two black spots over the eyes. The snake will encircle his neck and bite his cheeks and say, ‘I am your wealth, I am your treasure.’ “Then the Prophet recited the verse:
“And let not those who covetously withhold of the gifts which Allah has given them of His Grace, think that it is good for them: nay, it will be the worse for them; soon shall the things which they covetously withheld be tied to their necks like a twisted collar, on the Day of Judgment. To Allah belongs the heritage of the heavens and the earth; and Allah is well-acquainted with all that you do.” [Al-Imran 3: 180]. (Bukhari)
…Abide by the truth even though your mind deserts you.