Explanation of Riyad al-Salihin-83b

The Reciter: And upon his family and all his Companions.
The author (may Allah have mercy on him) transmitted in the context of the hadiths in "the chapter on the prohibition of belittling Muslims" from Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said:

It is sufficient evil for a man to look down on his Muslim brother.

بحسب امرء من الشر أن يحقر أخاه المسلم

Sunan Ibn Majah 4213Sahih (Darussalam)

It was narrated by Muslim.
And from Ibn Mas'ud (may Allah be pleased with him) from the Prophet (peace and blessings be upon him) who said

He who has in his heart the weight of a mustard seed of pride shall not enter Paradise.

لا يدخل الجنة من في قلبه مثقال ذرة من كبر

Sahih Muslim 91c

A man said: "Indeed, a man loves for his garment to be good and his sandal to be good." He said:

Verily, Allah is Graceful and He loves Grace. Pride is disdaining the truth (out of self-conceit) and contempt for the people.

إن الله جميل يحب الجمال الكبر بطر الحق وغمط الناس

Sahih Muslim 91a

Narrated by Muslim. And from Jundub ibn Abdullah (may Allah be pleased with him) who said: The Messenger of Allah (peace and blessings be upon him) said:

Once someone said: 'By Allah! Allah will not forgive such and such (a person).' Thereupon Allah, the Exalted and the Glorious, said: 'Who is he who takes an oath in My Name that I will not grant pardon to so-and-so? I have granted pardon to so-and-so and rendered your good deeds fruitless

قال رجل والله لا يغفر الله لفلان فقال الله عز وجل من ذا الذي يتألى علي ألا أغفر لفلان فإني قد غفرت له وأحبطت عملك

Riyad as-Salihin 1576

Narrated by Muslim. "

The Shaykh : In the name of Allah, the Most Gracious, the Most Merciful. These hadiths are in the explanation of the prohibition of looking down upon a Muslim. The discussion of the two verses that the author (may Allah have mercy on him) cited has already been mentioned.
As for these hadiths, it is the hadith of Abu Hurayrah that the Prophet (peace and blessings be upon him) said: This is an emphasis on the gravity of looking down upon a Muslim and that it is a great evil. If a person did not commit any evil other than this, it would be sufficient. So do not look down upon your Muslim brother, neither in his appearance, nor in his clothes, nor in his speech, nor in his character, nor in anything else. Your Muslim brother has great rights over you, so you must respect him and honor him. As for looking down upon him, it is forbidden, and it is not permissible for you to look down upon him.
Likewise, the hadith of Ibn Mas'ud and the hadith of Jundub ibn Abdullah (may Allah be pleased with them both); both indicate the prohibition of looking down upon a Muslim and that it is not permissible for you. Even when the Prophet (peace and blessings be upon him) mentioned in the hadith of Ibn Mas'ud that the Companions (may Allah be pleased with them) thought that if a person wore good clothing and put on a good sandal, that this was from arrogance, pride, and haughtiness. So the Prophet (peace and blessings be upon him) clarified to them that the matter is not so. He said: Beautiful in His essence (Exalted and Majestic is He), in His actions, and in His attributes. And He also loves beauty, meaning He loves adornment. So the more a person is adorned, the more beloved that is to Allah, provided that this adornment is within his means, meaning he is not poor and going to the extent of straining himself for beautiful clothes or a beautiful sandal, but rather Allah has bestowed upon him and he adorns himself. Then Allah the Exalted loves to see the effect of His blessing upon His servant. And likewise, the hadith of Sufyan ibn Abdullah, yes, Jundub ibn Abdullah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him and his family) informed [of] the hadith.
The student: ...

The Shaykh : Yes, he informed And this man was a worshipper who was pleased with his own deed and looked down upon his brother whom he saw as transgressing. So he swore that Allah would not forgive him. Then Allah the Mighty and Majestic said: And the favor is in the hand of Allah, He gives it to whom He wills. I have indeed forgiven him, and I have nullified your deed. I seek refuge in Allah. He spoke a word that destroyed his worldly life and his Hereafter; he perished because he said that while being pleased with himself and looking down upon his brother. So he swore that Allah would not forgive him. So Allah forgave that man because his sins were less than shirk, or because Allah the Exalted bestowed upon him and he repented. As for the other, his deed was nullified because he was pleased with his deed, and may Allah protect us from that, and he swore upon his Lord and affirmed that He would not forgive so-and-so. And Allah the Exalted is complete in sovereignty; no one swears upon Him. But if a person has good opinion of his Lord and swears upon Allah in a matter that does not involve transgression against others, then the Prophet (peace and blessings be upon him) said: And success is from Allah.
The student: ...

The Shaykh : Yes
The Reciter: And upon our master Muhammad, and upon his family and all his Companions.
He said (may Allah have mercy on him): "Chapter on the Prohibition of Showing Schadenfreude Over a Muslim. Allah the Exalted said:

The believers are but brothers

إنما المؤمنون إخوة

[Al-Hujurat 49:10]

And He said:

Indeed, those who like that immorality should be spread [or publicized] among those who have believed will have a painful punishment in this world and the Hereafter

إن الذين يحبون أن تشيع الفاحشة في الذين آمنوا لهم عذاب أليم في الدنيا والآخرة

[An-Nur 24:19]

From Wathilah ibn al-Asqa' (may Allah be pleased with him) who said: The Messenger of Allah (peace and blessings be upon him) said:

Do not rejoice over the mishaps of your brother so that Allah has mercy on him and subjects you to trials.

لاتظهر الشماتة لأخيك فيرحمه الله ويبتليك

Jami` at-Tirmidhi 2506Da'if (Darussalam)

Narrated by al-Tirmidhi, and he said: It is a good hadith.
Chapter on the Prohibition of Defaming Lineages Established in the Apparent Shari'ah. Allah the Exalted said:

And those who harm believing men and believing women for [something] other than what they have earned have certainly born upon themselves a slander and manifest sin.

والذين يؤذون المؤمنين والمؤمنات بغير ما اكتسبوا فقد احتملوا بهتانا وإثما مبينا

[Al-Ahzab 33:58]

"