Majma al-Zawaid — Hadith 17306

Salamah al-Kindi narrates: Sayyiduna Ali (may Allah be pleased with him) used to teach people the words for sending blessings upon the Prophet (peace and blessings be upon him), and he would recite: "O Allah! O Spreader of the earths! O Creator of the heavens! O You who prevail over hearts according to their natures, whether they be wretched or fortunate! Send down Your noble blessings, Your increasing blessings and Your kind favour upon Sayyiduna Muhammad (peace and blessings be upon him), who is Your servant and Your Messenger; he is the seal of those who have passed before (or: he is the one who ends the line of the earlier Prophets who were sent), and the opener of what is 'mughlaq' (that is, closed); he is the one who supports the truth by means of the truth, who prevails over the height of falsehood. He took up obedience to You under Your command, so that he might attain Your good pleasure, and in this his feet did not falter, nor did any weakness enter his resolve. He is the one who calls to Your revelation, who guards Your covenant and who strives in carrying out Your command, until he arranged a light for those seeking the light (of guidance). After the abundance of trials and sins, through him hearts were granted guidance, (a guidance) that came with clear signs, the light of Islam and the excellence of the rulings. So he is Your (appointed) trustee, who is ma'mun (that is, safeguarded from error), and he is the treasurer (that is, the guardian) of Your hidden knowledge, and he will be Your witness on the Day of Resurrection. Your sending him is a blessing; he is Your Messenger with the truth, who is a mercy. O Allah! Grant him a spacious place in Your justice, and through Your grace give him a manifold reward of goodness, in which there is congratulation and no turbidity, connected with the success of Your appointed reward and Your abundant giving. O Allah! Raise his building above the buildings of the people, honour him and host him in Your presence, perfect his light, and reward him for Your having sent him with this: that his testimony be accepted, his word be pleasing, and that he be the possessor of just speech, of decisive words (that is, the final word), of proof and of a mighty evidence."
Al-Tabarani recorded it in al-Mu'jam al-Awsat; the narration of Salamah al-Kindi from Sayyiduna Ali (may Allah be pleased with him) is 'mursal', and the remaining narrators of this report are the narrators of the 'Sahih'.