Narrated Anas reported God’s messenger as saying, “Three matters pertain to the root of faith:
no molestation of one who says there is no god but God, neither declaring him an infidel because of a sin, nor excommunicating him from Islam because of an action; jihad continues from the time God sent me till the last of this people fights with the dajjal, being annulled neither by the tyranny of a tyrannical ruler nor the justice of a just one; and belief in God’s decrees.”
Safwan b. ‘Assal told how, when a Jew said to his friend, “Let us go to this prophet,” his friend said to him, “Don’t say ‘prophet’, for if he heard you he would be greatly pleased.” 1 They went to God’s messenger and asked him about nine clear signs. God’s messenger said, “Do not associate anything with God. do not steal, do not commit fornication, do not kill anyone whom God has declared inviolate without a just cause, do not bring an innocent person before a ruler in order that he may put him to death, do not use magic, do not devour usury, do not slander a chaste woman, do not turn in flight on the day the army marches, and, a matter which affects you Jews particularly, do not break the Sabbath.” He said that thereupon they kissed/his hands and feet saying, “We testify that you are a prophet.” He asked “What prevents you from following me?” to which they replied, “David prayed to his Lord that prophets might never cease to arise from his offspring, and we are afraid that if we follow you the Jews will kill us.”
Abu Huraira reported that God's messenger said, “When a servant of God commits fornication faith departs from him and there is something like an awning over his head; but when he quits that action faith returns to him.”
Ibn ‘Umar reported God's messenger as saying, “The hypocrite is like a ewe which goes to and fro between two flocks, turning at one time to the one and at another time to the other.”