The Messenger of Allah (sallallahu `alayhi wa sallam) said, “Beware of suspicion (and ill-thinking), for it is the worst of false tales. Do not probe into each others affairs, and do not envy one another, and do not hate one another. But O’ slaves of Allah, be brothers!” [Sahih al-Bukhari & Muslim]
Kathir ibn Ziyad said, ‘I heard al-Hasan (al-Basri) say, “Do not ask about the good and bad deeds of your brother, for that is surely tajassus (probing, spying, finding fault etc).”‘
Abu Hatim: ‘The intelligent one must adhere to salvation by staying away from probing into the faults of people, and instead should preoccupy himself with his own faults. Surely, whoever preoccupies himself with his own faults instead of the faults of others, will find peace and relaxation in his being and his heart will not be exhausted. Whenever he looks to his faults and errors, then the similar faults of his brother will be easy for him to bear. However, whoever preoccupies himself with the faults of others instead of his own, then his heart will become blind, he will become tired out and he will forget his own shortcomings. The weakest of people is the one who criticizes others for what is in them, and the weakest from amongst them is the one who criticizes others for what is also within himself. And whoever criticizes others, will be criticized by them.’
Truthful was he who said:‘If you rebuke others, they’ll rebuke you and do so more!
And then what was hidden within you, will be on show.
Someone once said in some statement of the past,
A word containing wisdom and beauty so vast:
If ever you mention people, then leave behind their errors
For there is no error, except that yours can be said
If you criticize a people for what is not within them
Then that is mighty in the Sight of Allah and also men
And if you criticize them for what is also within you
Then how can the one-eyed rebuke the one-eyed too?
And how can people be criticized by someone who
His faults are worse when all faults are diffused?
When you look for other’s defects, you shall indeed find them
But remember that what is in you is far greater than them
So grant peace to the people, and leave them to themselves
For they can see your errors more than you can see yourself.’ Al-Shaybani mentioned that, “It is written in the Books that: ‘As you treat others, you shall be treated, and the cup you give to others, is the cup you shall drink from…’”
Abu Hatim: ‘Probing and seeking the faults of others is from the branches of hypocrisy just like thinking good of others is from the branches of faith. The intelligent one always has a good opinion of his brothers, and keeps his grief and sadness to himself. As for the ignorant one, he has evil opinion of his brothers and does not think about his crimes and distress.’
‘Abdullah ibn ‘Amr ibn al-’Aas (radhiallahu `anhu) said, ‘It is written in the Taurat that: “Whoever indulges in trade, becomes corrupt, and whoever digs an evil hole for his brother, will end up falling into it himself.”‘