It is completely within the Shari’ah (Islamic Law) to recite Salutations and Blessings upon Allah’s Messenger (sallallahu ‘alaihi wasallam) as is evident in the following Qur’aanic ayat : “Undoubtedly, Allah and His Angels send blessings on the Prophet (the Communicator of Unseen News), O you who believe ! Send upon him blessings and salute him fully well in abundance” (Surah al-Ahzab, Verse 56)
Almighty Allah in the Holy Qur’aan has enjoined the performance of many things by us such as Salaah, Fasting, Hajj etc. and has praised His Prophets and described their good qualities. He created Hadhrat Adam (‘alaihis salaam) and directed the Angels to do Sajda (prostration) to him. However, he does not say in any of His directions, “I (Allah) am doing it, therefore you should do likewise”. This honour was exclusively conferred upon our Beloved Nabi Hadhrat Muhammad (sallallahu ‘alaihi wasallam). Here, in the above verse, Almighty Allah at the very outset attributed Salawat (recital of blessings) on our Beloved Nabi Hadhrat Muhammad (sallallahu ‘alaihi wasallam), first to Himself (Sunnat-i-Ilaahi), then to His Angels (Sunnat-i-Malaa’ika), and after this enjoined on the Muslims (Sunnat-i-Mu’mineen) to do the same, by saying, “Undoubtedly, Allah and His Angels send blessings on the Prophet (the Communicator of Unseen News), O you who believe ! Send upon him blessings and salute him fully well in abundance”. There cannot be a greater honour for the Believers than this, who have been favoured with a share in this Divine performance with Almighty Allah and His Angels.
It is stated in the commentary of the Qur’aan, Tafseer-i-Rooh al-Bayaan, “Some ‘Ulama are of the opinion that the meaning of Allah’s blessing is, to raise Hadhrat Muhammad Mustapha (sallallahu ‘alaihi wasallam) to Maqaam-i-Mahmood (Glorious Station), the place from where he will intercede to Almighty Allah on behalf of his Ummat; the Angels’ blessing means their prayer for enhancing the position of Hadhrat Muhammad Mustapha (sallallahu ‘alaihi wasallam) and beseeching forgiveness for his followers. Blessings on the path of the believers means to obey, love and eulogize him.” Tafseer-i-Rooh al-Bayaan further states that the honour and reverance shown to Hadhrat Muhammad (sallallahu ‘alaihi wasallam) is of a much greater degree than shown to Hadhrat Adam (‘alaihis salaam) to whom only Angels were made to bow down (in honour). For in honouring Hadhrat Muhammad Mustapha (sallallahu ‘alaihi wasallam) Almighty Allah has also attributed it to Himself, whereas in the case of Hadhrat Adam (‘alaihis salaam) Almighty Allah asked only the Angels to show honour.
Having established and expounded on the injunction of the Holy Qur’aan we quote a few Ahaadith of the Holy Prophet (sallallahu ‘alaihi wasallam) pertaining to Salawat and Salaam.
Imam Tibraani (rahmat allahi ‘alaih) has recorded this Hadith narrated by Hadhrat Abu Darda (radi allahu ‘anhu) :
The Holy Prophet (sallallahu ‘alaihi wasallam) said : “Increase your recitation of DUROOD on me on Friday because on this day Angels present themselves to me. There is no servant of Allah who recites SALUTATIONS upon me, except that his voice reaches me from wherever he is”. The Companions asked even after your departure ? “He replied, Yes after my departure too, because Allah has made it Haraam upon the earth to consume the bodies of the Prophets”. (Jila-ul Ifhaam, by Ibn Qayyim)
“On Fridays recite the Salawat for me repeatedly ! The Salawat will be conveyed to me.” (Ibn Habbaan, Ibn Maaja, Abu Dawood)
When it was asked whether it would be conveyed to him after his Wisaal also, the Prophet (sallallahu ‘alaihi wasallam) answered, “Soil does not rot Prophets’ bodies. Whenever a Muslim says the Salawat for me, an Angel informs me of it and says, ‘So-and-so’s son, so-and-so of your Ummah sent his Salaam and prayed for you.'”
Sahl ibn Sa`d (radi allahu ‘anhu) narrates: Allah’s Messenger (sallallahu ‘alaihi wasalam) came out and met Abu Talha. The latter rose and went to him saying: “My father and mother be sacrificed for you, O Messenger of Allah! I see joy and delight in your countenance?” The Prophet (sallallahu ‘alaihi wasallam) said: “Yes, for Gabriel has just come to me saying: O Muhammad, whoever among your Community invokes blessings upon you once, Allah records for Him ten meritorious deeds, erases from his register ten evil deeds, and raises him ten degrees because of it.” (al-Sakhawi, al-Qawl al-badi` p. 107., al-Sakhawi said: “Our shaykh (Ibn Hajar) graded it hasan without doubt.”)
“Invoke blessings upon me abundantly on Friday because it is a day that is (particularly) witnessed and the Angels witness it (abundantly). As soon as a person invokes blessings on me his invocation is shown to me until he ends it.” Abu al-Darda’ (radi allahu ‘anhu) said: “Even after (your) death?” The Prophet (sallallahu ‘alaihi wasallam) replied: “Verily, Allah has forbidden the earth to consume the bodies of Prophets.” (Related by Ibn Majah with a sound chain through Abu al-Darda’. Also related with a sound chain from Aws ibn Aws al-Thaqafi by Ahmad, Ibn Abi Shayba, Abu Dawud, al-Nasa`i, Ibn Majah, al-Darimi, Ibn Khuzayma, Ibn Hibban, al-Hakim (sahih, confirmed by Dhahabi), Tabarani in his Kabir, and Bayhaqi in many places, some with the initial addition of the following: “The best of your days is Friday, for in it Adam was created, and in it his soul was taken back, and in it is the blowing of the Horn, and in it is the universal Seizure, therefore invoke blessings upon me abundantly on Friday,” etc. The first part (concerning the order to invoke more Salat on Friday and the disclosure of this invocation to the Prophet) is related by Bayhaqi in Shu`ab al-Iman through Abi Umama, Anas, and Abu Mas`ud al-Ansari, and by al-Hakim in his Mustadrak from the latter. Shafi`i in his Musnad relates the first part only (“Invoke blessings upon me abundantly on Friday”) mursal from Safwan ibn Salim.)
The Holy Prophet (sallallahu ‘alaihi wasallam) says in a Hadith, “Definitely there are many Angels of Allah that sojourn the earth and bring the Salaam of my Ummat to me”. (Narrated by Nisai and Ibn Habban)
Hadhrat ‘Abd ar-Rahman bin ‘Auf (radi allahu ‘anhu) says that one day the Holy Prophet (sallallahu ‘alaihi wasallam) came and entered a date garden. There he performed a very long prostration. Hadhrat ‘Abd ar-Rahman (radi allahu ‘anhu) feared that Allah had sent death to him. He drew close to him and began to look at him. The Holy Prophet (sallallahu ‘alaihi wasallam) raised his holy head from the prostration and asked what had happened to him, then he disclosed his fear to him. At this, the Holy Prophet (sallallahu ‘alaihi wasallam) said Hadhrat Jibra’il (‘alaihis salaam) asked whether he should not give him glad tidings that Allah said that He would send blessings to the person who recited the Holy Qur’an on him and peace and security to the person who bade Salutations to him. (Ahmad)
These are just a few Ahaadith. It is established beyond any doubt that the recitation of Salawat and Salaam has its origin in the Qur’aan and Hadith.