AL-WAHID (AL-AHAD)

Wahid: “The only being whose attributes of perfection encompass everything,
who is unique and indivisible.”

“He who has no partner in his attributes.”

Ahad: “The only being who is free from all deficiencies”
“He who has no partner in His essence.”

“And your Allah is One Allah. There is no god but He...” (al-Baqara, 2/163)

Wahid and Ahad both express the oneness of Allah.

Khatibi expresses the subtle difference between these two names as follows:

“Ahadiyyah is the unity of the essence while wahidiyyah aims to reject partnership in the attribute”

In the Nur Collection, the following explanation is given for Wahidiyyah and Ahadiyyah:

“As for unity (wahidiyyah), it is to say that all those creatures belong to One and they look to One and they are the creation of One. Whereas by oneness (ahadiyyah) is meant that most of the names of the Creator of all things are manifested in all beings.” (Nursi, Mektubat, p. 229.)

Allah is Wahid, He is one. His attributes encompass all creatures. Infinite power, infinite knowledge, absolute will... belong only to Him.

Allah is Ahad, one. He is the only one, the unique, the one and only, who is free from all the deficiencies in the essence of the creatures, all the deficiencies in their attributes, and all the helplessness in their actions, and is unlike any of them.

Allah is Wahid. His attributes of perfection have covered and encompassed everything.

He is the only power acting in all realms, and the only knowledge manifested in everything belongs to Him. All the stars in the sky, all the people, animals and plants in the world belong to Him. The seas, the rivers, the plains belong to Him. Jinn, spirits, angels belong to Him...

And Allah is Ahad; His essence is one. He has given each of His creatures a distinct essence and attributes peculiar to them, and He meets every need of His creatures personally and manifests many of His names on them.

How a person who believes in the oneness of Allah will practice this belief in the realm of deeds and what kind of mood he should have are pointed out in the book called Mektubat from the Nur Collection as follows:  

“Allah is One. Do not wear yourself out having recourse to other things; do not demean yourself and feel indebted to them; do not flatter them and fawn on them and humiliate yourself; do not follow them and make things difficult for yourself; do not fear them and tremble before them; for the Monarch of the universe is One, the key to all things is with Him, the reins of all things are in His hand, everything will be resolved by His command.” (Mektubat)