الَّذي يُؤتي مالَهُ يَتَزَكّىٰ
He who gives his wealth to purify himself.
EXEGESIS
Yatazakkā (purify himself) comes from tazkiyah, which can either mean to grow or to purify. Based on this, some have opted for the first meaning and thus the intended meaning would be that the God-wary is the one who gives his wealth for the sake of God seeking a virtuous growth, whilst others maintain that their intention is to be purified from all sorts of vice and sin. However, both meanings return to the same thing.
A minority of exegetes have also argued that yatazakkā means to give ritual zakat. As such, yatazakkā is an apposition (badal) to yuʾtī and clarifies the latter, i.e. the method of giving wealth is through paying zakat. This is only acceptable if these verses were revealed in Medina since the ritual zakat was not legislated in Mecca.
EXPOSITION
This verse is a description of the God-wary mentioned in the previous verse. It mentions that their intention when giving charity is to purify themselves. A similar description exists in 9:103 whereby the Prophet is commanded to receive zakat from the wealthy believers in order to purify them. There may be many people in society who give their wealth in charitable causes but what makes the God-wary stand out is their intention. They only seek spiritual growth, complying with the instructions of God, and purification from vices. They do not seek to show off or to gain power through their altruistic fame, or for anything but tazkiyah.
[1] Mizan, 20/307.
[2] Kashif, 7/576.
[3] Manahij, 30/536; Zamakhshari, 4/764.
[4] Mudarrisi, 18/156.