The Testimony of Tawhid
Allah bears witness, and verily, Allah is sufficient as a Witness, and He is the Most Truthful and Just Witness there is; His statement is the absolute truth,
أَنَّهُ لاَ إِلَـهَ إِلاَّ هُوَ
(that La ilaha illa Huwa) meaning, He Alone is the Lord and God of all creation; everyone and everything are His servants, creation and in need of Him. Allah is the Most Rich, Free from needing anyone or anything. Allah said in another Ayah,
لَّـكِنِ اللَّهُ يَشْهَدُ بِمَآ أَنزَلَ إِلَيْكَ
(But Allah bears witness to that which He has sent down (the Qur'an) unto you (O Muhammad )) 4:166.
Allah then mentioned the testimony of His angels and those who have knowledge after he mentioned His own testimony,
شَهِدَ اللَّهُ أَنَّهُ لاَ إِلَـهَ إِلاَّ هُوَ وَالْمَلَـئِكَةُ وَأُوْلُواْ الْعِلْمِ
(Allah bears witness that none has the right to be worshipped but He), and the angels, and those having knowledge (also bear witness to this)). This Ayah emphasizes the great virtue of those who have knowledge.
((He) maintains His creation in justice) in all that He does,
لاَ إِلَـهَ إِلاَّ هُوَ
(None has the right to be worshipped but He) thus emphasizing this fact,
(the Almighty, the All-Wise.) the Mighty that does not submit to weakness due to His might and greatness, the Wise in all His statements, actions, legislation and decrees.
The Religion with Allah is Islam
إِنَّ الدِّينَ عِندَ اللَّهِ الإِسْلَـمُ
(Truly, the religion with Allah is Islam.) Allah states that there is no religion accepted with Him from any person, except Islam. Islam includes obeying all of the Messengers until Muhammad who finalized their commission, thus closing all paths to Allah except through Muhammad. Therefore, after Allah sent Muhammad, whoever meets Allah following a path other than Muhammad's, it will not be accepted of him. In another Ayah, Allah said,
وَمَن يَبْتَغِ غَيْرَ الإِسْلَـمِ دِينًا فَلَن يُقْبَلَ مِنْهُ
(And whoever seeks a religion other than Islam, it will never be accepted of him) 3:85.
In this Ayah 3:19, Allah said, asserting that the only religion accepted with Him is Islam,
إِنَّ الدِّينَ عِندَ اللَّهِ الإِسْلَـمُ
(Truly, the religion with Allah is Islam.)
Allah then states that those who were given the Scripture beforehand divided in the religion after Allah sent the Messengers and revealed the Books to them providing them the necessary proofs to not do so. Allah said,
وَمَا اخْتَلَفَ الَّذِينَ أُوتُواْ الْكِتَـبَ إِلاَّ مِن بَعْدِ مَا جَآءَهُمُ الْعِلْمُ بَغْيًا بَيْنَهُمْ
(Those who were given the Scripture (Jews and Christians) did not differ except out of rivalry, after knowledge had come to them.) meaning, some of them wronged others. Therefore, they differed over the truth, out of envy, hatred and enmity for each other. This hatred made some of them defy those whom they hated even if they were correct. Allah then said,
وَمَن يَكْفُرْ بِآيَـتِ اللَّهِ
(And whoever disbelieves in the Ayat of Allah) meaning, whoever rejects what Allah sent down in His Book,
فَإِنَّ اللَّهِ سَرِيعُ الْحِسَابِ
(then surely, Allah is Swift in reckoning.) Allah will punish him for his rejection, reckon him for his denial, and torment him for defying His Book. Thereafter, Allah said.
(So if they dispute with you (Muhammad )) so if they argue with you about Tawhid,
فَقُلْ أَسْلَمْتُ وَجْهِىَ للَّهِ وَمَنِ اتَّبَعَنِ
(Say: "I have submitted myself to Allah (in Islam), and (so have) those who follow me'') meaning, Say, `I have made my worship sincere for Allah Alone without partners, rivals, offspring or companion,
(and those who follow me) who followed my religion and embraced my creed.' In another Ayah, Allah said,
قُلْ هَـذِهِ سَبِيلِى أَدْعُو إِلَى اللَّهِ عَلَى بَصِيرَةٍ أَنَاْ وَمَنِ اتَّبَعَنِى
(Say (O Muhammad ): "This is my way; I invite unto Allah with sure knowledge, I and whosoever follows me...'') 12:108.
Islam is the Religion of Mankind and the Prophet Was Sent to all Mankind
Allah commanded His servant and Messenger, Muhammad, to call the People of the Two Scriptures and the unlettered idolators to his religion, way, Law and all that Allah sent him with. Allah said,
وَقُلْ لِّلَّذِينَ أُوتُواْ الْكِتَـبَ وَالاٍّمِّيِّينَ ءَأَسْلَمْتُمْ فَإِنْ أَسْلَمُواْ فَقَدِ اهْتَدَواْ وَّإِن تَوَلَّوْاْ فَإِنَّمَا عَلَيْكَ الْبَلَـغُ
(And say to those who were given the Scripture (Jews and Christians) and to those who are illiterates (Arab pagans): "Do you (also) submit yourselves'' If they do, they are rightly guided; but if they turn away, your duty is only to convey the Message.) meaning, their reckoning is with Allah and their return and final destination is to Him. It is He Who guides whom He wills and allows whom He wills to stray, and He has the perfect wisdom and the unequivocal proof for all of this. This is why Allah said,
وَاللَّهُ بَصِيرٌ بِالْعِبَادِ
(And Allah sees the servants.) for He has perfect knowledge of who deserves to be guided and who does not deserve to be guided. Verily,
لاَ يُسْأَلُ عَمَّا يَفْعَلُ وَهُمْ يُسْـَلُونَ
(He cannot be questioned for what He does, while they will be questioned.) 21:23 because of His perfect wisdom and mercy. This and similar Ayat are clear proofs that the Message of Muhammad is universal to all creation, as it is well established in the religion, according to the various texts of the Book and Sunnah. For instance, Allah said,
قُلْ يَأَيُّهَا النَّاسُ إِنِّى رَسُولُ اللَّهِ إِلَيْكُمْ جَمِيعًا
(Say (O Muhammad ): "O mankind! Verily, I am sent to you all as the Messenger of Allah.'') 7:158, and,
تَبَارَكَ الَّذِى نَزَّلَ الْفُرْقَانَ عَلَى عَبْدِهِ لِيَكُونَ لِلْعَـلَمِينَ نَذِيراً
(Blessed be He Who sent down the criterion to His servant that he may be a warner to the `Alamin (mankind and Jinn).) 25:1.
The Two Sahihs and other collections of Hadith recorded that the Prophet sent letters to the kings of the earth during his time and to different peoples, Arabs and non-Arabs, People of the Book and the unlettered, just as Allah had commanded him. `Abdur-Razzaq recorded that Ma`mar said, that Hammam said that Abu Hurayrah said that the Prophet said,
«وَالَّذِي نَفْسِي بِيَدِهِ، لَا يَسْمَعُ بِي أَحَدٌ مِنْ هَذِهِ الْأُمَّةِ: يَهُودِيٌّ وَلَا نَصْرَانِيٌّ، وَمَاتَ وَلَمْ يُؤْمِنْ بِالَّذِي أُرْسِلْتُ بِهِ، إِلَّا كَانَ مِنْ أَهْلِ النَّار»
(By He in Whose Hand is my soul! No member of this Ummah, no Jew or Christian, hears of me but dies without believing in what I was sent with, but will be among the people of the Fire.) Muslim recorded this Hadith.
The Prophet said,
«بُعِثْتُ إِلَى الْأَحْمَرِ وَالْأَسْوَد»
(I was sent to the red and black. ) and,
«كَانَ النَّبِيُّ يُبْعَثُ إِلى قَوْمِهِ خَاصَّةً، وَبُعِثْتُ إِلَى النَّاسِ عَامَّة»
(A Prophet used to be sent to his people, but I was sent to all mankind.)