Having a deep belief in Allah and seeking Islam's straight path as much as one can are the ways to success in this world and hereafter. The Prophet's companions were the keenest people asking him about what benefits them in these two stages. In this hadith, the companion Sufian ibn Abdullah Ath-Thaqafy asked the Prophet ﷺ about an Islamic act that may save and suffice him away from other Islamic ones. He asked him about a comprehensive concept of all Islam's principles and objectives. This concept should guide and suffice him, complete his religion, and save him from Hell in the hereafter. The Prophet ﷺ said to him, “Say, ‘I believe in Allah’ then keep to the straight path.” It means to certainly say "I believe in Allah," and be upright while following the faith's guidance and requirements. Uprightness leads to all righteous deeds and prevents all evil acts. Thus, the hadith means being steadfast in faith with regularly performing righteous acts guiding us to the straight path. One of the uprightness' glad tidings is Allah's saying, "Indeed, those who have said, 'Our Lord is Allah' and then remained on a right course - the angels will descend upon them, [saying], 'Do not fear and do not grieve but receive good tidings of Paradise, which you were promised.'" (Fussilat: 30), and his saying, "Indeed, those who have said, 'Our Lord is Allah,' and then remained on a right course - there will be no fear concerning them, nor will they grieve. Those are the companions of Paradise, abiding eternally therein as reward for what they used to do." (Al-Ahqaf: 13, 14).