Praise be to Allah.
Al-Wakeel is al-Hafeez (the Preserver), al-Muheet (the One who encompasses all things). And it was said that it means al-Shaheed (the Witness).
He is the Sustainer Who guarantees provision for His slaves and Who protects their interests. The reality is that He controls all affairs independently. The powers of creation and command belong entirely to Him and no one else possesses anything of them. And it was said that it means al-Haafiz, Who guarantees to sustain all that He has created.
It was said that it means al-Kafeel (the Guarantor), and He is the best Guarantor to provide for us.
It was said that it means al-Kaafi (the Sufficient), and He is the most Sufficient.
Allaah says (interpretation of the meaning):
“and they said: ‘Allaah (Alone) is Sufficient for us, and He is the Best Disposer of affairs (for us).” [Aal ‘Imraan 3:173]
-- meaning, He is sufficient for us. Al-Wakeel in Arabic means the one who is entrusted to run the affairs of the one who entrusted them to him. The believers referred to in this aayah had entrusted their affairs to Allaah and put their trust in Him, so He described Himself as fulfilling that trust and them as having put their trust in Him, so He said, the Best Disposer of affairs for them. When a person puts his trust in his Lord, he submits to His Lordship and becomes a true slave of Him. Allaah has complete authority, meaning that al-Wakeel has full knowledge of that which has been entrusted to Him and He encompasses all its details; He has full power to deal with it and protect that which has been entrusted to Him, by His wisdom and His knowledge of how to deal with it in the most suitable manner.
Allaah is the One Who is above all shortcomings in any of His attributes; He is the Disposer of all affairs. This indicates that His knowledge encompasses all things and that He has perfect power to control all affairs with perfect wisdom, for He is the Best Disposer of Affairs.