It is narrated from Sayyiduna Abu Umamah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) used to swear by Allah three times without any exception: "There is no Muslim on the face of the earth who says in the morning: 'O Allah, to You belongs all praise; there is no god but You. You are my Lord and I am Your servant. I have believed in You, making my religion sincerely Yours. I have entered the morning upon Your covenant and Your promise as far as I am able. I turn to You in repentance from my evil deeds, and I ask Your forgiveness for my sins, which none forgives but You,' and then dies on that day, except that he will surely enter Paradise."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7848