Bukhari

Hadith Commentary:
This was a miraculous prophecy of the Prophet sallallahu alayhi wa sallam, which was fulfilled in its due time, and both Umar and Uthman radi Allahu anhuma drank from the cup of martyrdom.
The purpose of this is to express the virtue of Abu Bakr radi Allahu anhu. The trembling of Mount Uhud is indeed true, which manifested as one of the miracles of the Messenger sallallahu alayhi wa sallam.
From this, it is also evident that every single creature of creation possesses a sense of life within its own limits. Truly:
(“There is not a thing except that it glorifies Him with His praise.”) ()

Hadith Commentary:
➊
In one narration, it is mentioned that the Messenger of Allah (sallallahu alayhi wa sallam) struck his foot on Mount Uhud and uttered the aforementioned statement.
(Sahih al-Bukhari, Virtues of the Companions of the Prophet sallallahu alayhi wa sallam, Hadith: 3686)
➋
This was a miracle and prophecy of the Messenger of Allah (sallallahu alayhi wa sallam) which was fulfilled word for word at its appointed time; thus, both Umar (radi Allahu anhu) and Uthman (radi Allahu anhu) drank from the cup of martyrdom, and Abu Bakr (radi Allahu anhu) attained the station of Siddiqiyyah (truthfulness).
➌
The purpose of this hadith is to state the virtue of Abu Bakr (radi Allahu anhu), and also that the trembling of Mount Uhud is indeed true, which manifested as a miracle of the Messenger of Allah (sallallahu alayhi wa sallam).
➍
It is also evident from this that all things created by Allah Ta’ala are, within their own limits, endowed with a consciousness of life, as is stated in the Word of Allah Ta’ala:
"Everything glorifies Allah Ta’ala, but you do not understand their glorification."
(Bani Isra’il: 44: 17)

Hadith Commentary:
➊
The noble Companions (radi Allahu anhum ajma'in), after giving preference to the two Shaykhs—Abu Bakr (radi Allahu anhu) and Umar (radi Allahu anhu)—and Uthman (radi Allahu anhu) over the other Companions, did not give preference to any among the remaining Companions over one another. When they exercised ijtihad (independent reasoning) in giving preference, the virtues of these three individuals would become prominent.

➋
Most likely, by this is meant those eminent Companions (radi Allahu anhum ajma'in) with whom the Messenger of Allah (sallallahu alayhi wa sallam) would consult in important matters. At that time, Ali (radi Allahu anhu) was young and had not yet reached the stage of old age. By this, there is absolutely no intention of belittling Ali (radi Allahu anhu) or of delaying his precedence in virtue after Uthman (radi Allahu anhu). Rather, it is the belief of Ahl al-Sunnah that after the three Caliphs, Ali (radi Allahu anhu) is the most virtuous, then the remaining six of the ten given glad tidings (al-‘asharah al-mubashsharah), then those who participated in Badr and Uhud, and after them those who pledged allegiance at Ridwan. The interpretation mentioned in this hadith is very necessary.
And Allah knows best.

Hadith Commentary: Regarding the virtues of the Caliphs, the Prophet (sallallahu alayhi wa sallam) stated in advance: By "martyrs" here, what is meant are Umar and Uthman (radi Allahu anhuma).

Hadith Commentary:
The scholars of spiritual wayfaring (suluk) have written:

When the mountain of Uhud began to tremble, the Messenger of Allah (sallallahu alayhi wa sallam) deemed it necessary to clarify that the trembling of this mountain was not like that of Mount Tur when it moved with the people of Musa (alayhis salam) after they committed distortion in the words of Allah.

At that time, the mountain trembled due to the intensity of wrath, whereas the trembling of Uhud was out of joy and delight, because upon it were those personalities whom Allah loves. It is as if the mountain of Uhud was swaying with happiness and, through its state, was saying:

O mountains! Upon you are stones, but upon me is the Prophet.
Upon you are trees, but upon me is the beloved child of Amina.
Upon you are houses, but upon me is the Prophet of the Last Age.

Therefore, when the Messenger of Allah (sallallahu alayhi wa sallam) commanded it to be still, it became still.

Explanation:
1:
By "two martyrs" is meant: Amr and Uthman (radi Allahu anhuma), both of whom were testified as martyrs by the tongue of the Messenger (sallallahu alayhi wa sallam). Whoever denies their acceptance in the court of Allah should fear for his own faith.
Such a person is not only no longer a "believer," he is not even a Muslim.