Bukhari

Hadith Commentary:
➊
In this hadith, the importance of facing the qiblah is highlighted, in such a way that whoever prays as we do, our prayer includes bowing (ruku‘), prostration (sujud), and also facing the qiblah. However, this incidental mention was not considered sufficient; rather, facing the qiblah was stated independently.
In this way, its particularity, virtue, and significance become evident, and attention is drawn to the fact that the qiblah has been chosen.
The reason for this is that these three things create a distinction between Muslims and non-Muslims.
Prayer and facing the qiblah are religious distinctions, because in other religions, firstly, their prayer is not like our prayer.
Secondly, their prayer does not include facing the qiblah.
The third distinction is eating slaughtered meat (dhabihah), which is a social distinction, because followers of other religions do not consume our slaughtered meat.
Thus, these three things serve as symbols (shi‘ar) for Muslims.
If nothing is apparent that would necessitate disbelief by adopting it, then the one who adopts these things will be considered a Muslim.
This does not mean that only these three things are sufficient for being a Muslim; rather, the meaning is that those who, along with the other necessities of the religion, maintain these distinctions are Muslims.

➋
Whoever denies the necessities of the religion (daruriyyat al-din) is no longer among the people of the qiblah.
By necessities of the religion are meant those things that are established by the Book of Allah, the Sunnah of the Messenger of Allah (sallallahu alayhi wa sallam), and the consensus (ijma‘) of the Ummah.
All beliefs, actions, obligations, and supererogatory acts established by these three sources—having faith in all of them and accepting them is called the necessities of the religion. Denial of them or false interpretation is disbelief (kufr). For example:
Performing prayer is obligatory, believing in its obligation is also obligatory, and learning it is also obligatory; ignorance of it or denial is disbelief.

➌
During prayer, it is necessary to face the qiblah; however, in a state of excuse or fear, its obligation is lifted. Similarly, there is some concession regarding this in voluntary (nafl) prayers when performed on a riding animal.
(Fath al-Bari: 1/644)

These are the outward characteristics of a Muslim. After the declaration of the two testimonies (shahadatayn), among the acts of worship, it is only the prayer (salah) that can serve as a distinguishing sign of Islam, because fasting (sawm) is a hidden matter, whereas zakat is not obligatory upon everyone. Moreover, zakat is only due once a year. Hajj, on the other hand, is only obligatory once in a lifetime, and even then, not upon everyone. Furthermore, since prayer exists in all religions, the distinction of the Muslims’ prayer will be through the direction of the qiblah, because every religion has its own qiblah. After acts of worship, the next level is that of transactions and social conduct. Among the disbelievers, there was no concept of lawful (halal) and unlawful (haram); nor did they differentiate between an animal slaughtered (dhabihah) and a dead animal (maytah). Slaughtering in the name of Allah is a particular characteristic of a Muslim; therefore, he is a Muslim who eats the animal slaughtered in the name of Allah, whether he slaughters it himself or someone else does. This is a social sign of Muslims and is apparent. The remaining signs are hidden, and thus they were not mentioned. And Allah knows best.

Takhrij al-Hadith:
[صحيح بخاري 391]

Fiqh al-Hadith
➊ The meaning of being under the responsibility of Allah and His Messenger is that such a person is under the protection, covenant, and guarantee of Allah and His Messenger. His life and property will be safeguarded. He will be granted all the same rights that are available to ordinary Muslims. However, if he commits a crime for which the punishment is death, then the Muslim ruler or judge can have him executed. Similarly, if he commits acts that nullify Islam (nawāqid al-Islām), then after proof and the establishment of evidence, his fundamental rights will be revoked.

➋ It is clearly evident from this hadith that in the religion of Islam, actions are judged by their outward appearance. That is, a person who outwardly performs the pillars of Islam is considered a Muslim; therefore, the outward rulings of Islam will be applied to him. As for the matter of being a Muslim and obedient inwardly, only Allah knows that.

➌ Along with faith (iman), actions are also necessary, whereas the Murji’ah hold the false belief that actions are not necessary along with faith. This hadith is also a clear refutation of the Murji’ah.

➍ From this hadith and other evidences, it is established that prayer (salah) should be performed in the same manner as the Messenger of Allah (sallallahu alayhi wa sallam) (and the noble Companions, radi Allahu anhum) performed it.

➎ The rulings of the people of Islam apply to the people of the qiblah, except if they commit clear disbelief (kufr sariḥ) and acts that nullify Islam (nawāqid al-Islām). There is consensus among all Muslims that the followers of Mirza Ghulam Qadiani the liar—Qadiani, Mirzai, and Lahori—all are excluded from the people of Islam (the people of the qiblah), are disbelievers, and are non-Muslims. Likewise, those whose disbelief and non-Muslim status is established by the Book and the Sunnah and consensus (ijma‘) are also excluded from the people of the qiblah and the people of Islam.