A believer is not a fault-finder and is not abusive, obscene, or course.

Bismillaahir Rahmaanir Raheem

As Salamu Alaykum Wa Rahmatullaahi Wa Barkaatuh

A believer is not a fault-finder

Hadith - Bukhari's Book of Manners #313,
Ahmad, Ibn Hibban, and Hakim

... 'Abd Allah reported that the 
Prophet of Allah (Sallallahu alaihi wasallam) said,

 "A believer is not a fault-finder
and is not abusive, obscene, or course."

***

Hadith - Bukhari's Book of Manners #329

... Ibn 'Abbas (radiAllahu anhu) said, 

"If you wish to mention the faults of your friend,
mention your own faults first."

***

Hadith - Bukhari's Book of Manners #330

... Ibn 'Abbas (radiAllahu anhu) said
on the following verse of the Qur'an, 

"Nor defame one another"
(49:11), 
"Do not spend your time finding fault with one another."

***

Hadith - Bukhari's Book of Manners #545

Jubayr ibn Nufayr reported that
Mu'adh ibn Jabal (radiAllahu anhu) said, 

"If you love someone, do not quarrel with him
and do not annoy him.
Do not ask others about him,
for the one you ask might be his enemy
and thus tell you things about him
that are not true and thus break you apart."

***

Hadith - Bukhari's Book of Manners #889 and Ibn Hibban

'Amr ibn al 'As (radiAllahu anhu) said, 

"...I am amazed at one
who spots an impurity in the eye of another
but is unable to detect it in his/her own eye,
or who attempts to remove
a grudge from another's heart
while making no attempt to remove
grudges from his/her own heart.
I have never blamed anyone
for the confidences of mine
that they have betrayed.
How could I,
when already they have given me
reason for pause?"

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