3. This means the Spirit of Prophethood with which a Prophet is imbued in order to fulfill his mission by word and deed. The Quran has called this the Spirit in several places, for this has the same relation to the mission of a Prophet and his moral life, which the soul has to the physical human life.
4. As one of the things, which prompted the disbelievers to challenge the Prophet (peace be upon him) for scourge, was their presumption that he was not a true Prophet. Allah told them categorically that he was a true Prophet who had been imbued with the Spirit which We had sent down on him.
“Spirit of His command, upon whom He wills.” This is the answer to the objections which the chiefs of the Quraish used to raise against the Prophet (peace be upon him): Had Allah wanted to send a Messenger to them, was there no one better than Muhammad (peace be upon him), son of Abdullah, for this mission. Why did He not choose one of the big chiefs of Makkah or Taif for the purpose? Such absurd objections needed no other answer than this that is why such an answer has been given in several places of the Quran as if to say: Allah knows best how to do His work, and does not stand in need of any advice from you. He chooses for His mission anyone whom He considers fit for it.
5. This verse declares the essence of the Spirit of Prophethood, which is this: Godhead belongs to one Allah alone, so only He is worthy of fear. Therefore, there is no other anchor that might make fast and hold together human moral system than His fear. For it is the fear of His displeasure and His punishment, and the fear of the consequences of His disobedience which alone can act as a strong deterrent to restrain one from deviation. That is why mankind has been admonished: Fear Me.