This verse speaks of one of the basic aspects of the prophethood which is among the fundamental tenets of Islam. That is, the Holy Prophet ﷺ has been sent as His Messenger to the entire mankind and to the jinn (genies) coming into being upto the day of judgment.
This verse has commanded the Holy Prophet ﷺ to make general declaration that he has been sent to all the people of the world, and that his prophethood was not limited to a particular people and place as was the case with the early prophets who came to a particular people and place and for a limited period of time.
He is the last of all Prophets (علیہم السلام)
The fact that the Holy Prophet ﷺ has been sent down at the end of all prophets is an obvious reason behind the Islamic belief of Finality of prophethood. His being the last of all prophets and coming down for the guidance of all people of all future times leaves no room for any other Prophet. The same fact provides with an explanation to a characteristic quality of the Muslim Ummah. According to a Tradition of the Holy Prophet ﷺ ، there shall always be a group among the Muslims who will keep defying the anti-Islamic forces and putting resistance in the way of sacrilegious thought and practice. It will also correct false interpretations of the Qur'an and the Sunnah. This group shall be favoured by Allah with His special help and thereby will, ultimately, win over the opposite forces. It is because these people are considered to be the real inheritors of the prophetic mission, faithfully discharging their duty after the Holy Prophet ﷺ .
Imam al-Razi, under the comments of the Qur'anic commandment كُونُوا مَعَ الصَّادِقِي (Be in the company of the truthful) has remarked that this phrase has provided an assurance that a group of the truthful shall always be available for people, otherwise the command of seeking their company made no sense. Imam Razi has inferred the principle of consensus (اِجمَاع) from this phrase. That is, the presence of the truthful people was enough to preclude the agreement of the Muslim Ummah on error.
Ibn Kathir has inferred from this verse it has provided a proof that the Holy Prophet ﷺ was the seal of and for prophets (علیہم السلام) because his message was for all the people of the world the ages to come. According to some authentic Traditions, the Prophet 'Isa (علیہ السلام) will also follow the Law of the Holy Prophet ﷺ after his descent from heavens in the last age. Apart from this verse there are many other verses which speak in unmistakable terms of the Finality of Prophethood. For example the Holy Qur'an said:
وَأُوحِيَ إِلَيَّ هَـٰذَا الْقُرْآنُ لِأُنذِرَكُم بِهِ وَمَن بَلَغَ
"And this Qur'an has been revealed to me that I may warn you thereby, and whomsoever it may reach." (6:19)
This, evidently, enjoins the following of the Holy Qur'an upon all the people coming after the Holy Prophet ﷺ and to acquire knowledge of the Qur'an.
Some distinctions of the Holy Prophet ﷺ
Ibn Kathir has cited the Musnad of lmam Ahmad reporting by authentic narrators that at the occasion of the battle of Tabuk, the Holy Prophet ﷺ was engaged in the late night prayer (Tahajjud). The companions gathered around him in a circle to save him from any possible attack by the enemy. After completing the prayer the Holy Prophet ﷺ said, "This night I have been awarded with five distinctions, not awarded to any prophet before. Firstly, my prophethood has been extended to all mankind while the message of the prophets prior to me was limited to their particular.
Secondly, my presence creates a feeling of dread in the hearts of my enemy which overtakes him from a distance of one month's travel. Thirdly, the spoils taken from the enemy have been made permissible for my people, while it was prohibited for the early people. Fourthly, Allah has made the whole earth a place for our prayers like a mosque, and made it a purifier (in tayammum) for my people, while the prayers of the early people was limited to their churches or synagogues. They were not permitted to pray at home or out in the land. Besides, in the absence of water my people allowed to make use of soil, in place of water for tayammum (a substitute of ablution). The early people were not given this concession." Then, he said, emphatically that the fifth distinction was, above all, the most promising and helpful. He explained, "Every prophet was asked by Allah to make one particular supplication which was to be essentially acceded to, and every prophet made that invocation for their particular aim. Allah asked me too to make such invocation. I preferred to reserve my invocation until the Day of Judgment which will be of great use to you and to those who follow and bear witness that there is no god but Allah."
Another Tradition reported by Imam Ahmad on the authority of the Companion Abu Musa al-Ash'ari ؓ has contained that the Holy Prophet ﷺ said, "Any one hearing the news of my appearance, be he a Muslim, Christian or Jew must believe in me, otherwise he will be placed in Hell."
Sahih al-Bukhari has reported the following incident with regard to this verse: Sayyidna Abu Bakr and Sayyidna ` Umar ؓ once had severe disagreement on a matter. Sayyidna ` Umar ؓ left the place to express his dissent. Sayyidna Abu Bakr ؓ followed him in order to bring him round. Sayyidna ` Umar ؓ being angry with him entered his house and locked the door upon him. Sayyidna Abu Bakr ؓ having no choice went to the Holy Prophet ﷺ and related the whole story to him. Later, Sayyidna ` Umar ؓ had a feeling of regret for misbehaving Sayyidna Abu Bakr ؓ ، he too went to the Holy Prophet ﷺ and informed him of the incident. The Companion Abu al-Darda' ؓ عنہ has reported that the Holy Prophet ﷺ was annoyed at it. Seeing that Sayyidna ` Umar ؓ was going to be admonished for it, Sayyidna Abu Bakr ؓ said to the Holy Prophet ﷺ ، "My fault was greater". At this point the Holy Prophet ﷺ said, "Can you people not leave one of my companions alone and save him from the annoyance on your part? Do you people not know when I declared by the will of Allah يَا أَيُّهَا النَّاسُ إِنِّي رَسُولُ اللَّـهِ إِلَيْكُمْ جَمِيعًا "0 people, I am a messenger of Allah sent to you all," you all belied me? It was Abu Bakr alone who testified to my Prophethood."
In short, this verse is a clear evidence proving that the Holy Prophet ﷺ has been sent to the whole mankind. His message is for all generations and for all times to come and for all places. No one can achieve salvation without believing in him, even if he is faithfully and devotedly practicing some other faith or book.
The next sentence of the verse reminds people that he has been sent from the One to Whom the Kingdom of the heavens and the earth belongs and Who gives life to every living creature and brings death to it. That is, He alone is the Lord of the Universe. The last sentence of the verse said:
آمِنُوا بِاللَّـهِ وَرَسُولِهِ النَّبِيِّ الْأُمِّيِّ الَّذِي يُؤْمِنُ بِاللَّـهِ وَكَلِمَاتِهِ وَاتَّبِعُوهُ لَعَلَّكُمْ تَهْتَدُونَ
"So, believe in Allah and His Messenger, the Ummi (unlettered) prophet who believes in Allah and in his words, and follow him so that you may get the right path."
After establishing the fact that the Holy Prophet ﷺ was sent for all the people of the world and for all times to come, and that there is no other choice for anyone but to follow his law - the Islam, the verse enjoins the belief in Allah and in His Messenger, who is Ummi, the unlettered. He, himself believes in Allah and in His words. The people should, therefore, follow him to keep themselves on the right path.
The 'words' کلمات refer to the word of Allah revealed to his prophets like the Torah, Evangel (the book revealed to the Prophet 'Isa (علیہ السلام) (Jesus) ) and the Qur'an. It may be noted that the command of believing in him is followed by another command of following him. This has indicated that sheer belief or making the verbal utterances of belief, is not enough for guidance or salvation. Practicing Islamic Shari'ah is essentially required for one's salvation in the Hereafter.
The great saint and spiritual leader Sheikh Junaid of Baghdad has remarked that all the paths leading to Allah are closed except the path specifically defined by the Holy Prophet ﷺ .