ʿArafah, and the best that I and the prophets before me have said is: ‘None is worthy of worship but Allah alone, with no partner. His is the dominion, and His is all praise, and He has power over all things.’”

In al-Tirmidhī and elsewhere, he is reported to have said:

“Whoever dies knowing that none is worthy of worship but Allah will enter Paradise.”

In the Sahīh, it is reported that he said to his uncle as death approached:

“My uncle, say, ‘None is worthy of worship but Allah’—a declaration with which I may plead your case before Allah.”

The evidence is abundant and mutually reinforcing that the greatest good deed is affirming Allah’s oneness, just as the worst evil deed is associating partners with Him. This is the sin that Allah does not forgive, as He, the Exalted, says:

“Indeed, Allah does not forgive associating partners with Him, but He forgives anything less than that for whom He wills.”

Affirming His oneness is the good deed that necessarily brings bliss to the one who possesses it. This is established in the authentic hadith concerning the two determining causes: that which entails bliss and that which entails misery. Whoever dies testifying that none is worthy of worship but Allah will enter Paradise, whereas whoever dies associating anything with Allah will enter the Fire. In the hadith, he also described this declaration as the highest branch of faith.

In the two Sahīh collections, it is reported that he—may Allah bless him and grant him peace—said to the delegation of ʿAbd al-Qays:

“I command you to have faith in Allah. Do you know what faith in Allah is? It is to testify that none is worthy of worship but Allah and that Muhammad is the Messenger of Allah, to establish prayer, to give zakat, and to pay one-fifth of the spoils.”

He thus included these deeds within faith, while also including them within Islam in the authentic hadith of Gabriel. When Gabriel came to him in the form of a Bedouin and asked him about faith, he replied:

“Faith is to believe in Allah, His angels, His Books, His messengers, and resurrection after death, and to believe in divine decree, both its good and its evil.”

He then asked him about Islam, and he replied:

“It is to testify that none is worthy of worship but Allah and that Muhammad is the Messenger of Allah