The Prophets, peace be upon them, were sent to establish the proof

 I take refuge with Allaah from the accursed devil. 
بِسْمِ اللَّهِ الرَّحْمَـنِ الرَّحِيمِ
  Bismillah-ir-Rahman-ir-Raheem: In the name of Allah, the Compassionate, the Merciful. 
  Welcome to my blog and praise the Magnificent Lord as you enter: Allahu Akbar: Allah is the Greatest .
  May the Peace and Blessing of Allah Azza wa Jal, our Lord Glorified and Praised be He, be upon our beloved  Prophet, his Family, and Companions.
The Prophets, peace be upon them, were sent to establish the proof.
إِنَّآ أَوْحَيْنَآ إِلَيْكَ كَمَآ أَوْحَيْنَآ إِلَى نُوحٍ وَالنَّبِيِّينَ مِن بَعْدِهِ وَأَوْحَيْنَآ إِلَى إِبْرَهِيمَ وَإِسْمَـعِيلَ وَإْسْحَـقَ وَيَعْقُوبَ وَالاٌّسْبَاطِ وَعِيسَى وَأَيُّوبَ وَيُونُسَ وَهَـرُونَ وَسُلَيْمَـنَ وَءَاتَيْنَا دَاوُودَ زَبُوراً
(163. Verily, We have sent the revelation to you as We sent the revelation to Nuh and the Prophets after him; We (also) sent the revelation to Ibrahim, Isma`il, Ishaq, Ya`qub, and Al-Asbat, (the offspring of the twelve sons of Ya`qub) `Isa, Ayyub, Yunus, Harun, and Sulayman; and to Dawud We gave the Zabur.)
 وَرُسُلاً قَدْ قَصَصْنَـهُمْ عَلَيْكَ مِن قَبْلُ وَرُسُلاً لَّمْ نَقْصُصْهُمْ عَلَيْكَ وَكَلَّمَ اللَّهُ مُوسَى تَكْلِيماً
 (164. And Messengers We have mentioned to you before, and Messengers We have not mentioned to you, and to Musa Allah spoke directly.)
 رُّسُلاً مُّبَشِّرِينَ وَمُنذِرِينَ لِئَلاَّ يَكُونَ لِلنَّاسِ عَلَى اللَّهِ حُجَّةٌ بَعْدَ الرُّسُلِ وَكَانَ اللَّهُ عَزِيزاً حَكِيماً
(165. Messengers as bearers of good news and warning, in order that mankind should have no plea against Allah after the (coming of) Messengers. And Allah is Ever All-Powerful, All-Wise.)
Surah 4 An Nisa verse 163-165
Tafsir Ibn Kathir
Muhammad bin Ishaq narrated that Muhammad bin Abi Muhammad said that `Ikrimah, or Sa`id bin Jubayr, related to Ibn `Abbas that he said, “Sukayn and `Adi bin Zayd said, `O Muhammad! We do not know that Allah sent down anything to any human after Musa.’ Allah sent down a rebuttal of their statement,
(Verily, We have inspired you (O Muhammad) as We inspired Nuh and the Prophets after him.)” Allah states that He sent down revelation to His servant and Messenger Muhammad just as He sent down revelation to previous Prophets. Allah said,
(Verily, We have inspired you (O Muhammad) as We inspired Nuh and the Prophets after him,) until,
(…and to Dawud We gave the Zabur. ) The `Zabur’ (Psalms) is the name of the Book revealed to Prophet Dawud, peace be upon him.
Allah said,
(And Messengers We have mentioned to you before, and Messengers We have not mentioned to you) Before the revelation of this Ayah. The following are the names of the Prophets whom Allah named in the Qur’an. They are: Adam, Idris, Nuh (Noah), Hud, Salih, Ibrahim (Abraham), Lut, Isma`il (Ishmael), Ishaq (Isaac), Ya`qub (Jacob), Yusuf (Joesph), Ayyub (Job), Shu`ayb, Musa (Moses), Harun (Aaron), Yunus (Jonah), Dawud (David), Sulayman (Solomon), Ilyas (Elias), Al-Yasa` (Elisha), Zakariya (Zachariya), Yahya (John) and `Isa (Jesus), and their leader, Muhammad . Several scholars of Tafsir also listed Dhul-Kifl among the Prophets. Allah’s statement,
(and Messengers We have not mentioned to you,) means, `there are other Prophets whom We did not mention to you in the Qur’an.’
Allah said,
(and to Musa Allah spoke directly.) This is an honor to Musa, and this is why he is called the Kalim, he whom Allah spoke to directly. Al-Hafiz Abu Bakr bin Marduwyah recorded that `Abdul-Jabbar bin `Abdullah said, “A man came to Abu Bakr bin `Ayyash and said, `I heard a man recite (this Ayah this way): وَكَلَّمَ اللَّهَ مُوسَى تَكلِيمًا “and to Allah, Musa spoke directly.” Abu Bakr said, `Only a disbeliever would recite it like this.’ Al-A`mash recited it with Yahya bin Withab, who recited it with Abu `Abdur-Rahman As-Sulami who recited it with `Ali bin Abi Talib who recited with the Messenger of Allah ,
(and to Musa Allah spoke directly.)”’ Abu Bakr bin Abi Ayyash was so angry with the man who recited the Ayah differently, because he altered its words and meanings. That person was from the group of Mu`tazilah who denied that Allah spoke to Musa or that He speaks to any of His creation. We were told that some of the Mu`tazilah once recited the Ayah that way, so one teacher present said to him,  What would you do concerning Allah’s statement,
(And when Musa came at the time and place appointed by Us, and his Lord spoke to him,) [7:143]” The Shaykh meant that the later Ayah cannot be altered or changed.
Allah said,
(Messengers as bearers of good news as well as of warning,) meaning, the Prophets bring good news to those who obey Allah and practice the good things that please Him. They also warn against His punishment and torment for those who defy His commandments. Allah said next,
(in order that mankind should have no plea against Allah after the Messengers. And Allah is Ever All-Powerful, All-Wise.) Allah sent down His Books and sent His Messengers with good news and warnings. He explained what He likes and is pleased with and what He dislikes and is displeased with. This way, no one will have an excuse with Allah. Allah said in other Ayat,
(And if We had destroyed them with a torment before this, they would surely have said: “Our Lord! If only You had sent us a Messenger, we should certainly have followed Your Ayat, before we were humiliated and disgraced.”) and,
(And if (We had) not (sent you to the people of Makkah) in case a calamity should seize them for (the deeds) that their hands have sent forth. ) It is recorded in the Two Sahihs that Ibn Mas`ud said that the Messenger of Allah said,
(No one is more jealous than Allah. This is why He prohibited all types of sin committed in public or secret. No one likes praise more than Allah, and this is why He has praised Himself. No one likes to give excuse more than Allah, and this is why He sent the Prophets as bearers of good news and as warners.) In another narration, the Prophet said,
(And this is why He sent His Messengers and revealed His Books.)