Al-Matalib al-'Aliyah 447 — The opening supplication and other matters

It is narrated from Sayyiduna Rifa'ah bin Rafi' (may Allah be pleased with him) (one of the Companions who took part in the Battle of Badr) that he said the takbir in his prayer and then recited this supplication: 'Allahu akbar, Allahumma laka al-hamdu kulluhu, wa laka al-mulku kulluhu, wa ilayka yarji'u al-amru kulluhu, as'aluka min al-khayri kullihi, wa a'udhu bika min al-sharri kullihi' (Allah is the Greatest. O Allah, all praise belongs to You alone, all sovereignty is Yours alone, and to You all matters return. I ask You for every kind of good, and I seek refuge in You from every kind of evil).
I (Ibn Hajar) say: Imam Bukhari (may Allah have mercy on him) recorded in his Sahih, through Adam, from Shu'bah, from Husayn, from Ibn Shaddad, that he said: "I saw Sayyiduna Rifa'ah bin Rafi' al-Ansari (may Allah be pleased with him), and he had been present at Badr." The rest of its chain meets the condition of Imam Bukhari. Although this narration here is not marfu' (that is, it is the statement of a Companion), I think that it has the ruling of marfu' (that is, its ruling is like a saying of the Prophet (peace and blessings be upon him)). In another chain, it is narrated from Abdullah bin Shaddad bin al-Had (may Allah have mercy on him) that he heard one of the Companions of the Prophet (peace and blessings be upon him), called Sayyiduna Rifa'ah bin Rafi' (may Allah be pleased with him), relate that when he entered the prayer and said the takbir, he said words like the supplication mentioned above.
This hadith is sahih (authentic).