And those who pay the Zakah.
Most commentators say that the meaning here is the Zakah that is paid on wealth, even though this Ayah was revealed in Makkah, and Zakah was ordained in Al-Madinah in the year 2 H.
The apparent meaning is that the Zakah that was instituted in Al-Madinah is the one based upon the Nusub and the specific amounts, apart from which it seems that the basic principle of Zakah was enjoined in Makkah. As Allah says in Surah Al-An`am, which was also revealed in Makkah;
وَءَاتُواْ حَقَّهُ يَوْمَ حَصَادِهِ
but pay the due thereof on the day of their harvest, (6;141)
It could be that what is meant here by Zakah is purification of the soul from Shirk and filth, as in the Ayah;
قَدْ أَفْلَحَ مَن زَكَّـهَا
وَقَدْ خَابَ مَن دَسَّـهَا
Indeed he succeeds who purifies himself (Zakkaha). And indeed he fails who corrupts himself. (91;9-10)
It could be that both meanings are intended, purification of the soul and of one's wealth, because that is part of the purification of the soul, and the true believer is one who pays attention to both matters.
And Allah knows best.
And Allah says;
وَالَّذِينَ هُمْ لِفُرُوجِهِمْ حَافِظُونَ