Whoever performs our prayer, faces our Qiblah (direction of the Ka‘bah), and eats from our slaughtered animals—that is the Muslim who enjoys the protection (covenant) of Allah and His Messenger. So do not betray Allah by violating His protection

Ibn Rajab said: This Hadīth indicates that a person's blood is not protected merely by uttering the two testimonies of faith until he fulfills their obligations. The greatest of these obligations is prayer; hence, it was mentioned specifically. In another Hadīth, Zakah is added alongside prayer.
People's affairs are judged according to what is outward, not what is hidden; so whoever outwardly manifests the symbols of Islam is treated as a Muslim, unless something contrary to that becomes evident.
Ibn Rajab said: Mentioning the facing of the Qiblah indicates that one must perform the prayer prescribed for the Muslims in their Book revealed to their Prophet—the prayer directed toward the Ka‘bah. Otherwise, whoever prays toward Bayt al-Maqdis, as the Jews do after it was abrogated, or toward the east, as the Christians do, is not a Muslim, even if he declares the testimony of Tawhīd (monotheism).
It contains evidence of the great importance of facing the Qiblah in prayer, for no other condition of prayer was mentioned besides it, such as purification and the like.
Ibn Rajab said: Mentioning the eating of the Muslims' slaughtered animals indicates the necessity of adhering to all the outward laws of Islam. Among the greatest of these is eating what Muslims slaughter and agreeing with them in this matter; therefore, whoever abstains from it is not considered a Muslim.