"Actions are (judged) by motives (niyyah), so each man will have what he intended. Thus, he whose migration (hijrah) was to Allah and His Messenger, his migration is to Allah and His Messenger; but he whose migration was for some worldly thing he might gain, or for a wife he might marry, his migration is to that for which he migrated." - Amirul Mu'minin, 'Umar bin al-Khattab
Imam Rabbani Mujaddid Alf-Sani Shaykh Ahmad Farooqi Sarhindi
Imam Rabbani (may Allah have mercy on him) was born of Friday night in 97 A.H. in Sirhind, a town in the province of Punjab, India. He bore the name Shaykh Ahmad while Mujaddid Alf-Sani is his appellation. By his descent he is related to Hazrat Umar Farooq (May Allah be blessed with him).
He was an Indian Islamic scholar from Punjab and a prominent member of the Naqshbandi Sufi order. He is described as Mujaddid Alf Thani, meaning the "reviver of the second millennium", for his work in rejuvenating Islam.
Mektubat is the common term referred to the letters of sufi shaykhs and scholars. The Mektubat of Shaykh Ahmad Sirhindi are indeed the most popular among the letters of sufi shaykhs. This book is a classic and most venerated book of sufism that covers classical sufism, methodologies, beliefs and practices of Islam and contains many other spiritual secrets. His letters were compiled in his lifetime and placed in three volumes.