The Book Dalaa'ilul Khairaat was written by the pious Sufi and scholar Sheikh Abu Abdullah Muhammad Ibn Sulaiman Al-Jazuli Rahimahullah (d. 870/1466). He grew up amongst the Berbers of North Africa in Sus and later moved to Fez where he studied Fiqh and memorized the Mudawwana of Imam Malik Rahimahullah. 

More than twenty thousand students learnt Tafseer and Fiqh from him and many narrated hadith from him. He was initiated into the Shaazili order of Sufism and remained in solitary retreat for fourteen years. When he emerged many were attracted to him and thousands repented from their lives of sin through him.

One day while he was travelling with his students he arrived at a village close to Fez. The time for Zuhr Salaah was coming to an end and they had no water to perform wudhu. Finally they stumbled upon a well but there was no rope or bucket to draw the water from it. The Sheikh became worried that the Salaah time would pass and began walking around the well anxiously. In the meanhile, an eight year old girl was observing the proceedings from a nearby house.

She called out : "O Sheik, why the anxiety?"
The Sheikh replied: "I am Muhammad Ibn Sulaiman Al-Jazuli. The time of Zuhr is about to elapse and I have no water to perform wudhu."

In surprise the girl answered : "You are such a great personality. How can it be that you cannot do such a simple thing as draw water from a well! Wait,

I will come to help you."

When the girl arrived she spat into the well and the water began to gush forth on all four sides of the well. She then returned home. When the Sheikh had completed his Salaah he immediately went to the house of the little girl and knocked on the door. The little girl asked : "Who is it?"

The Sheikh replied: "O beloved girl, by the Oath of that Being who has created and guided you and in the Name of Allah, all the Prophets and Muhammad Sallallahu Alaihi Wasallam, whose intercession you are hopeful of, please inform me how you have reached this high level of piety." 

The girl replied : "Had you not taken such a noble oath I would never have told you. I have reached this level by a certain durood which I recite regularly."

The Sheikh learnt the durood from her and he immediately felt a strong desire in his heart to write a book on durood written with the most beautiful words.

The book he wrote is called Dalaa'ilul Khairaat. It has been printed and recited in many parts of the Muslim world especially in the blessed cities of Makkah and Madina. Many commentaries on it have been written in Arabic and Urdu. 

Sheikh Sulaiman Al-Jazuli Rahimahullah passed away while in sajda during Fajr Salaah. Seventy years after his death his body was transferred to another location in Morocco. Amazingly his body was completely intact. Allahu Akbar. May Allah reward him with the highest stages in Jannah. Aameen! 

References :

1. Dalaa'ilul Khairaat
2. Al'ilaam Lizzarkali