It was requested from the great master of the Path, famous for the transmission of the invocation of the Supreme Divine Name, Mawlānā Abu'l Abbās Shaykh Sīdī Ahmad ibn Mustafa al-`Alawī al-Mustaghānimī, may Allah grant us and the Muslims his good-pleasure and extend his life, that he compose some words dealing with the prayer of benediction (salawāt) upon the Prophet [sallallahu `alahyi wa sallam], explicating its profound meanings. So he responded to this request - may Allah be ever-pleased with him - saying:

The Branching Out of Secrets in the Exposition of the Meaning of Benedictions Upon the Chosen Prophet
Shaykh Abu'l Abbās Ahmad ibn Mustafa al-`Alawī