Zakah (alms) is one of the five pillars of islam. Its importance can be realized from the fact that in 82 verses of the qur’an Zakah is associated with prayer (Salah), such as :
Establish regular prayer and give Zakah; and  obey Allah and his messenger. Quran (33:33)

If social justice and compassion to fellow humans who are disadvantaged is one of the central themes in the message of Allah to humanity,

Then it is no wonder that Zakah, like prayer and fasting, was also enjoined upon the people of the past messengers:
And we made them ( descendants of Abraham ) leaders, guiding by our command, and we sent them inspiration to do good deeds, to establish regular prayers and to practice Zakah; and they constantly served us. Quran (21:73)

The Benefits 0f Giving  Zakah
1.. It Purifies Your Wealth As Allah Ta’ala Says in The Qur’an:
Take alms from their wealth in order to purify them and sanctify them with it and pray for them. Quran (9:103)

2.. It keeps one away from sin and saves the giver from the moral ill arising from the love and greed of wealth.

3.. Through Zakah, the poor are cared for, these include widows, orphans, the disabled, the needy and the destitute.

Zakah is the right of the poor. Zakah is not considered a favor that is given to the poor by the rich. It is the right of the poor on the wealth of the rich. Allah says:
..(In their) wealth there is a known share for the beggars and the destitute. Quran (70:24-25)

Zakah, therefore, is unlike charity that is given to the needy voluntarily. Withholding Zakah is considered depriving the poor of their due share. Thus one who pays Zakah actually ” Purifies ” his wealth by separating from it the portion that belongs to the poor.