Abu Huraira reported that a man came and questioned the Prophet. He said:

``O Muhammad, inform me what is Islam?'' The Prophet said: ``Islam is that you should worship Allah alone and do not associate anyone with Him, keep up prayer, give in charity (Zakaat), perform the Pilgrimage (Hajj) to Makka and fast during Ramadaan.''

He asked, ``If I do all this, will I become a Muslim?'' The Prophet said: ``Yes.''

(Sunan Nasa'i, vol. iii, p. 366 of edition used)

Umar related that the Angel Gabriel came to the Holy Prophet and said:

``O Muhammad, tell me what Islam is?'' The Holy Prophet said:

``Islam is that you testify that there is no god but Allah, and that Muhammad is the messenger of Allah, and keep up prayer, give in charity (Zakaat), fast in Ramadaan, and perform the Pilgrimage ( Hajj) if you are able to.''

( Muslim, Book of Faith, p. 76 of edition used)

``A man said to Ibn Umar: Why do you not do jihad? He said: I heard the messenger of Allah, peace and blessings of Allah be upon him, say, Islam is based on five things: Testifying that there is no god but Allah, keeping up prayer, giving in charity, the Pilgrimage, and fasting in Ramadaan.''

(Muslim, Book of Faith, vol. i, p. 93)

Anas related that a man came to the Holy Prophet and said:

``Your emissary came to us, and said that you claim that Allah has sent you.'' The Holy Prophet replied: ``He spoke the truth.'' He said: ``The emissary asserted that five daily prayers have been made obligatory for us.'' The Holy Prophet replied: ``He spoke the truth.'' The man said: ``Has Allah commanded you this?'' The Holy Prophet said ``Yes.'' [The man then questioned the Holy Prophet about charity, fasting and Pilgrimage, in the same way]. The man then turned to go, saying: ``By Him Who sent you, I shall do no more or less than this.'' The Holy Prophet said: ``If he spoke the truth, he shall enter paradise.''

(Sahih Muslim, vol. i, pp. 86,--,87)

The Holy Prophet said:

``Whoever says prayers as we do, and faces our Qibla, and eats the meat slaughtered by us, he is a Muslim, for whom is the covenant of God and the covenant of the messenger of God, so violate not the covenant of God.''

(Bukhari, Book of Prayer; Book 8, ch. 28; vol. i, p. 222)

The Holy Prophet said:

``Whoever testifies that there is no god but Allah, and faces our Qibla, and prays as we pray, and eats the meat slaughtered by us, he is a Muslim who has the rights of a Muslim and the duties of a Muslim.''

(Bukhari, Book of Prayer; ibid.)

Not only in books of Hadith accepted by the Ahl Sunna, but also in the collections accepted by the Shiahs a very similar definition of a Muslim is given. Ali, the fourth Caliph, announced during his rule:

``He who faces our Qibla, and eats the meat slaughtered by us, and believes in our Prophet, and testifies our testimony [i.e. the Kalima], and enters our religion, we shall apply to him the law of the Quran and the Islamic limitations, and no such person shall be superior to another one [in rights].''

(Faruh Kafi, vol. iii, Book of rejection, p. 166)

A man spoke very impertinently to the Holy Prophet. The account continues:

``Khalid Ibn Walid said: O messenger of Allah, shall I strike off his neck? The Holy Prophet said: No, maybe he says his prayers [i.e. is a Muslim]. Khalid said: Many performers of prayer there are who say with their tongues that which is not in their hearts. The Holy Prophet said: I have not been commanded to open out people's hearts and cut open their insides [to see what is their intention].''

(Bukhari, Book of Expeditions; Book 64, ch. 63; vol. ii, p. 657)

``Usama related: The Holy Prophet sent us on an expedition against the Huraqa. We attacked them in the morning and defeated them. I and a Christian found one of their men. When we surrounded him he said: There is no god but Allah. The Christian stopped at this, but I hit the man with my spear till I killed him. When we returned and this news reached the Holy Prophet, he said: Usama, you killed him after he said, `There is no god but Allah?' I said: He was trying to save his life. But the Holy Prophet kept on repeating this till I began to wish that I had not become a Muslim before that day.''

(Bukhari, Book of Expeditions, ch. The sending of Usama to the Huraqa; Book 64, ch. 47)

This shows that a recital of the Kalima is sufficient for a person to be regarded as a Muslim. The Holy Prophet's repetition of his reprimand, even after Usama's explanation, shows that even if there is reason to suspect that a person is insincere in his profession of the Kalima, he is still to be regarded as a Muslim.

``Ibn Abbas related that a man of the Banu Sulaim tribe passed by a party of the Companions of the Holy Prophet [on an expedition], and he had his goats with him. He offered salaam [assalamu alaikum] to them...They said, He has offered salaam to save himself. So they stopped and killed him, and took his goats. They brought these to the Holy Prophet, so Allah revealed: 'O you who believe! When you go forth [to fight] in the way of Allah, make investigations, and do not say to anyone who offers you} assalamu alaikum, You are not a believer'.''

( Tirmizi, ch. Tafsir al-Quran under Sura 4; see Arabic-Urdu edition of Maulana Badi-uz-Zaman, Muhammad Ali publisher, Karachi, vol. ii, p. 416; see also Bukhari, Book of Commentary on the Quran; Book 65, ch. 18 under Sura 4; vol. ii, p. 764)

In all these hadith, it is taught that there is no need to investigate deeply into the beliefs held by a person to determine whether he is a Muslim. One need only look as some aspects of his apparent conduct. If he is seen praying in the manner of the Muslim prayer, facing in the direction in which Muslims face, or if he is heard proclaiming the Kalima, for example, then he is a Muslim.