Al humzah refers to the one who slanders by speech and al lammaz refers to one who salander by acion
Quranic scholars are of the opinion thant the surath was revealed against Akhnas bin shuraiq. Some others have the opinion that it was revealed against walid bin muqayyara who used to backbite the holy prophet and made sarcastic ramarks and mocked him.
The first verse of the surat shows tha strongest terms of a threatening nature. Thought these are some references ,it is said that the meaning is a general one.
Slanderer and backbites referred in the verses are those who sting others with their speech behavior or sarcasm at their backs or in front of them. They mock the people and defame them with evil motives.
The prophet sa has said:
“ The worst people among allahs’ slaves are those who wonder with slanders, those who make many among friends and those who spread bad news against innocents ”
From the islamic point of view, the honour of others is regarded highly respectable ,hence anything that causes them to be insulted is a great sin. Prophet s says: the lowest one among people is he who insults people.