Asalam-u-Alaikum
I think that the following text that I found in a website with the Qur'anic verses and Hadiths about Khatemiyyat can be useful.
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End of the Prophethood, Prophet Muhammad (s.a.w.w) for a Muslim is:
No single tenet of Islam protects the perfect and universal religion of ALLAH (s.w.t) from corruption and innovation better than the doctrine of the finality of Prophethood. In more than one hundred of its verses, the Holy Quran has made it abundantly clear that no new prophet or prophetic revelation will be sent to humanity. For instance, ALLAH has declared:
"Muhammad is not the father of any man among you, but he is the Apostle of ALLAH and the Last of the Prophets". ( 33 : 40 ) Al-Quran.
The Last Prophet, Muhammad (s.a.w.w), has also explained this point in over two hundred Ahadith. For instance, the Messenger of ALLAH has taught:
"My position in relation to the prophets who came before me can be explained by the following example: A man erected a building and adorned this edifice with great beauty, but he left an empty niche in the corner where just one brick was missing. People looked around the building and marveled at its beauty, but wondered why a brick was missing from that niche. I am like unto that one missing brick and I am the last in the line of the Prophets". (Bukhari, Muslim, Musnad Ahmad, Tirmizi, Musnad Abu Dawud).
"There will arise thirty impostors in my Ummah (followers) and each one of them will pronounce to the world that he is a prophet, but I am the last in the line of the Prophets of God and no Prophet will come after me". (Abu Dawood).
"I am Muhammad, I am Ahmad, I am the effacer and infidelity shall be erased through me; I am the assembler. People shall be assembled on Doomsday after my time. And I am the last in the sense that no prophet shall succeed me". (Bukhari, Muslim, Tirmizi).
"...O People, no prophet will come after me, and no new faith will be born. Reason well, therefore, O People, and understand my words which I convey to you...". (Sermon delivered on the ninth day of Dhul-Hajj 10 A.H. and witnessed by 120,000 Muslims).
Prior to Islam, a new prophet was generally commissioned when the teachings of earlier prophets were lost, corrupted, or required some modification. However, the holy Quran clearly states that the dispensations of Islam are universal, final, completed, perfected, and protected. For instance, we read:
"Say (O Muhammad): 'O Mankind! Lo! I am the Messenger of ALLAH to you all, (the Messenger) of Him unto Whom belongs the Sovereignty of the heavens and earth". ( 7 : 158 ) Al-Quran.
"...This day I have perfected your religion for you, completed my favor upon you and have chosen for you Islam as your way of life". ( 5 : 3 ) Al-Quran.
The Holy Quran, Hadith, Tafseer, and the opinion of the Companions (r.a) have been consistent on this point, since the advent of Islam. In fact, the first rightly guided Caliph, Hazrat Abu Bakr (r.a), supported by all companions of the holy Prophet (s.a.w.w), waged a war against the false claimant to Prophethood, Musailma the Kazzab (liar), despite the fact that the Muslim state was still in its infancy and without the necessary means. Those taught by the holy Prophet (s.a.w.w) were absolutely certain of this doctrine and the need to protect the religion of humanity from corruption. Indeed, three times as many Muslims willingly sacrificed their precious lives fighting Musailma, as had during the entire mission of the holy Prophet (s.a.w.w). This act of Hazrat Abu Bakr (r.a) was so highly regarded, endorsed and accepted by the companions, that Hazrat Umar (r.a) proposed:
"I will exchange all good deeds of my life time for your acts of one night and one day. One night from those three nights you spent with Prophet Muhammad (s.a.w.w) in the Cave of "Saur" and one day from the days of battles against impostor prophets to guard the Finality of Muhammad". (Mishkawt).
Throughout ages, great scholars, Mujaddids, and jurists of Islam have also unanimously agreed on absolute finality of Prophethood. Sheikh Mulla Ali Qari (r.t.a), for instance, has written:
"Muhammad (s.a.w.w) is "Khatim-un-Nabiyeen" meaning the Last of the Prophets (a.s) and that on Him all sorts of Nubuwwat (Prophethood) came to an end. This is supported by definite arguments and clear injunctions and is one of the fundamental beliefs of Islam. Rejection of this doctrine is an obvious disbelief and an ugly deviation".
The great jurist of Islamic Law, Imam Abu Hanifah (r.t.a), has ruled. Once a person claimed that he is a Prophet of ALLAH. Imam Abu Hanifah (r.t.a) made an announcement;
"Anyone who demands proof from him (a claimant to Prophethood) will become a Kafir (disbeliever), as Prophet Muhammad (s.a.w.w) has emphatically said: 'No Prophet will come after me". (Manaqib Abi Hanifah).
Every believer is advised to remain mindful of this fundamental teaching of Islam and the activities of misguided organizations, like Qadyani (Ahmadi) and many other movements, whose leaders reject this clear decree of ALLAH and selfishly strive to divide mankind, misguide the uninformed, and create a following for their organization.
Just as there is no deity worthy of worship but ALLAH, there is no Prophet after Muhammad (s.a.w.w), and no revelation after the Holy Quran. With ALLAH is Success and Peace of ALLAH be upon his final Messenger, Muhammad (s.a.w.w), His family, Companions (r.a), and sincere followers till the Day of Judgment.
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I do not believe that any other statement is required after this. This proves that Prophet Muhammad(P.B.U.H) is the last and final prophet of Allah(SWT). In the verse( 5 : 3 ) in which Allah(SWT) says that Allah(SWT) had completed/perfected the religion. After this, anyone who alters it is going against the commandment of Allah(SWT).
Also, I would like to ask what kind of a logic would it be to believe in something, so much so that you adopt the identity provided by it, and go against the very fundamental belief/commandment.
