Nasai

Hadith Commentary:
(1)
There are two types of standing (qiyam) for a funeral (janazah):
➊ Standing upon seeing a funeral.
➋ Those accompanying the funeral remain standing.
In this chapter, Imam Bukhari rahimahullah has discussed the first type of standing for a funeral.

In the early period of Prophethood, people would stand when a funeral passed by, but later this practice was abandoned; therefore, now this standing is not obligatory. As Hazrat Ali radi Allahu anhu states, the Messenger of Allah sallallahu alayhi wa sallam commanded us to stand for the funeral, but afterwards he himself began to sit and instructed us to remain seated as well.
(Musnad Ahmad: 1/82)

Similarly, when a funeral passed by Hazrat Hasan and Hazrat Ibn Abbas radi Allahu anhuma, Hazrat Hasan radi Allahu anhu stood up, but Hazrat Ibn Abbas radi Allahu anhu remained seated. Hazrat Hasan said: "Did not the Messenger of Allah sallallahu alayhi wa sallam use to stand?" Upon this, Sayyiduna Ibn Abbas radi Allahu anhu replied that he used to stand, but then he began to sit.
(Sunan an-Nasa'i, Al-Jana'iz, Hadith: 1925)

Due to these ahadith, if someone remains seated upon seeing a funeral, it is permissible.

Hadith Commentary:
From this hadith, Imam Bukhari rahimahullah has established that when a funeral procession (janazah) passes by a person who is sitting, he should stand up until it has passed him or until it is placed on the ground.

The hadith scholars (muhaddithin) have written various reasons for this.
➊ Some are of the opinion that one should stand due to the awe inspired by death, because seeing a funeral reminds one of death.
➋ Some have said that angels accompany the funeral, so one should stand out of respect for them. However, whatever the reason may be, in our view, the command to stand upon seeing a funeral was given earlier.
➌ The Messenger of Allah sallallahu alayhi wa sallam eventually discontinued this practice. Despite this, it is reported from some of the noble Companions radi Allahu anhum that they would stand upon seeing a funeral.
➍ It is possible that the news of this discontinuation did not reach them.
And Allah knows best.

Benefits and Issues:
However, in other narrations it is mentioned that later the Prophet (sallallahu alayhi wa sallam) gave the command to sit instead of standing.
Therefore, Shaykh al-Albani and others have considered the command to stand as abrogated, while some scholars have accepted the permissibility of both practices.

Benefits and Issues:

➊
When a person is sitting on the road
and a funeral procession comes by, he should stand up.
When the funeral has passed, he may sit down.

➋
Abdullah ibn Abbas (radi Allahu anhu) declared this practice abrogated, because the Messenger of Allah (sallallahu alayhi wa sallam) sometimes did not stand up.
Ali (radi Allahu anhu) also said the same. (Sunan Ibn Majah, Hadith: 1544)
However, these two hadiths can also be reconciled in such a way that standing up is not considered obligatory,
but rather it is considered recommended (mustahabb, i.e., better).

➌
What is the wisdom in standing up upon seeing a funeral? Two reasons are mentioned in the hadith:
One is that death is such a thing
that it causes a person to be saddened and distressed,
and the remembrance of the Hereafter brings fear upon the heart.
To express this, one should stand up upon seeing a funeral. (Sunan Ibn Majah, Hadith: 1543)
The second reason is to honor the angels who are with the funeral.
In Sunan al-Nasa’i, it is narrated from Anas (radi Allahu anhu)
that when a Jewish funeral passed by, the Prophet (sallallahu alayhi wa sallam) stood up and said: “I stood up because of the angels.” (Sunan al-Nasa’i, al-Jana’iz, Chapter: The concession regarding leaving standing, Hadith: 1931)

➍
Those who are with the funeral
should not sit down until the bier is placed on the ground.
It is narrated from Abu Sa’id al-Khudri (radi Allahu anhu) that the Messenger of Allah (sallallahu alayhi wa sallam) said: “When you see a funeral, stand up.
Whoever accompanies it should not sit down until (the bier)
is placed on the ground.” (Sahih al-Bukhari, al-Jana’iz, Chapter: Whoever follows a funeral should not sit until it is placed down from the shoulders of men, and if he sits, he is ordered to stand, Hadith: 1310)

Benefit:
In this hadith, it is stated that upon seeing a funeral procession, one should stand up. However, this hadith is abrogated; its abrogating hadith is found in Sunan Abi Dawud (2719) and Sunan Ibn Majah (1545). Now, it is permissible to remain seated upon seeing a funeral procession.