Tirmidhi

Explanation:
1:
That is, whoever causes unjust harm to a Muslim in terms of wealth, life, or honor and dignity, Allah, the Exalted, will inflict upon him a similar harm. Likewise, whoever disputes unjustly with a Muslim, Allah will send hardship upon him.

Benefits and Issues:
Benefit: No Muslim brother should, in any way, cause harm, hardship, or loss to his fellow Muslim brother in particular; otherwise, there is a risk of becoming the target of the supplication against (bad du'a) by the Prophet of Allah (sallallahu alayhi wa sallam).

Benefits and Issues:
➊
Our esteemed researcher has declared the mentioned narration weak in terms of its chain of transmission, whereas other scholars have considered it hasan (good) on the basis of supporting evidences, as our researcher himself has also mentioned its other supporting narrations, though he has not indicated towards their weakness or authenticity. In any case, due to these supporting evidences, the mentioned narration is actionable and a valid proof.
For further details, see: (al-Mawsu‘ah al-Hadithiyyah, Musnad al-Imam Ahmad: 25/34, 35, and al-Irwa’ by al-Albani, no. 896)

➋
Muslims should be considerate of each other's comfort and ease, and should not attempt to cause harm to anyone.

➌
Allah, the Exalted, will cause him harm or will make things difficult for him.
This could mean that He will punish him on the Day of Resurrection and will call him to account strictly.
And it could also mean that he will receive his punishment in this world itself, that as a punishment from Allah, he will be surrounded by difficulties and will suffer loss.
And Allah knows best.

Takhrij:
There is some weakness in the chain, the hadith is hasan li-ghayrihi.
[ابوداود 3635],
[ ترمذي 1940]
The wording «مسلما » is not found in Tirmidhi.
The well-known hadith «لا ضرر ولا ضرار» “Neither is it permissible to cause harm initially, nor to retaliate in obstinacy” supports this.
For further evidences, see Irwa’ al-Ghalil [896] and also refer to: [تحفته الاشراف 9/228 ]

Vocabulary:
«ضَارَّ» is from the bab mufā‘alah (form III verb). A person who intentionally and deliberately causes harm to someone is called «مضار». If someone causes harm in order to obtain a right, or for the purpose of a hadd (prescribed punishment) or ta‘zir (discretionary punishment), or if harm is caused to another unintentionally, then this is not «مُضار».
«شَاقَّ» is also from the bab mufā‘alah of «شِقْ», meaning to oppose someone in confrontation, such that one is on one «شِق» (side) and the other is on the opposite «شِق»; in «ومن يشاقق الرسول الخ » as well, this is the intended meaning.

Benefits:
➊ A Muslim is a friend of Allah and Allah is his friend «اللَّهُ وَلِيُّ الَّذِينَ آمَنُوا» and He said «فَسَوْفَ يَأْتِي اللَّهُ بِقَوْمٍ يُحِبُّهُمْ وَيُحِبُّونَهُ». Now, it is evident that whoever causes harm to a friend of Allah, how could Allah, exalted is He, ever tolerate it? And it is also a principle that the recompense is of the same nature as the deed; therefore, whoever deliberately causes harm to a Muslim in his life, wealth, honor, or anything else, Allah, exalted is He, will cause harm to him. And whoever, without reason, takes to opposing a Muslim and harbors enmity against him, Allah, exalted is He, will impose hardship upon him.
➋ Abu Surmah radi Allahu anhu is a Companion who is well-known by his kunyah; there is much difference regarding his name. He was from Banu Mazin bin Najjar and participated in Badr and the battles thereafter. [سبل ]

Takhrij:
«أخرجه أبوداود، القضاء، باب في القضاء، حديث:3635، والترمذي، البر والصلة، حديث:1940، لؤلؤة يوثقها غير الترمذي.»©Explanation:
➊ The aforementioned narration has been declared weak in its chain (isnad) by our esteemed researcher, whereas other scholars have graded it as hasan (good) due to supporting narrations (shawahid). Furthermore, in his research on Sunan Ibn Majah, our esteemed researcher has also mentioned its supporting narrations, but did not indicate their authenticity or weakness.
Therefore, from the statements of the scholars, the preferred opinion appears to be that the aforementioned narration is of hasan (good) status due to supporting narrations.
And Allah knows best.
For further details, see: (Al-Mawsu‘ah al-Hadithiyyah, Musnad al-Imam Ahmad: 25/34, 35; and Irwa’ al-Ghalil by al-Albani, no. 896)

➋ In this hadith, warning has been given against harming and causing distress to a Muslim: that whoever causes harm to a Muslim, oppresses him, or disputes with him unjustly and without reason, then Allah, exalted is He, will inflict hardship upon him.

© Narrator of the Hadith:
«حضرت ابوصرمہ رضی اللہ عنہ » belonged to the tribe of Mazin, hence he was called Mazani.
His name was Malik bin Qays or Qays bin Malik.
He participated in Badr and other battles.
A few ahadith are narrated from him.