Deliverance of last message?

يَا أَيُّهَا الرَّسُولُ بَلِّغْ مَا أُنزِلَ إِلَيْكَ مِن رَّبِّكَ ۖ وَإِن لَّمْ تَفْعَلْ فَمَا بَلَّغْتَ رِسَالَتَهُ ۚ وَاللَّهُ يَعْصِمُكَ مِنَ النَّاسِ ۗ إِنَّ اللَّهَ لَا يَهْدِي الْقَوْمَ الْكَافِرِينَ

O Messenger! Deliver what bas been revealed to you from your Lord; and if you do it not, then you have not delivered His message, and Allah will protect you from the people; surely Allah will not guide the unbelieving people.

Verse Number 67 Sura Al-Maeda (Table Spread) Chapter 6 AlQuran ul Hakeem, from order of descend and revelation it is second but last verse revealed.
Question is what that importance announcement was? The none declaration of that message even amounting to discrediting all effort and struggles of Mohammad SAWA in the path of Allah Almighty, all Merciful and Beneficent. Why Prophet should have been apprehended of delaying the announcement. From whom he had been afraid off and why? If it was some religious ritual, rule or law, why he should hesitate, he had announced, his Prophet hood, five times prayers, prayers of late night (Tahajad), thirty days fastings and above all fighting and warring for Islam. Nothing is more important and precious than life. Battles took place even between, father and sons, brother and uncles against nephews and vice verse. It means it was even serious than giving life. By that time even last hurdle conquest of Mecca and surrender of Quraish has already achieved. There was conversion and acceptance of Islam by infidels (even if no way was left to escape). By then every body was a Muslim so from whom Mohammad SAWA be apprehended  of rejection and annoyance? 

This discussion is wide open now: -

Soon after Holy Prophet performing his Haj and staying a few more days at Mecca, was returnning to Medina, on his way back delivers his Last Public Sermon, Khutaba tul Widah, declaring the completion of his job, declaring equality of human beings, no effect of skin color, race or wealth, gender and age. The Emman and trust: is in faith and belief and not in race, language, color, sex, age or wealth. He put forth the social norms and wisdoms. Next day, Caravans strated moving for their native home lands. The people of Mecca used to accompany The Piligrims and say them good bye at this point on outskirts of Mecca at a cross road. Here there were four routes, one back to Mecca, one on wards towards Medina and Syria and Iraq, one towards right to Taif and inside Najad, and one toward left to (now Jiddah) and Eden (Yemen). Few caravans had already left for their on onward journey. Here on 18^th Zil Hajja 10^th AH, this Verse (Aya) is revealed asking Prophet to deliver Allah's message. Prophet SAWA was reluctant to reveal. In a stern and strong warning Allah says,”If he SAWA does not deliver this message, Prophet SAWA has done nothing and it will amount to as if he had not delivered any message at all” So what was the importance of this message and why Prophet SAWA was thinkful, reluctant and apprehended, what was so special about this message? Prophet summoned different messengers and sent them to those, who had already left for their home journey, to be called back. In the mean while asked people to arrange a address system, asked for erecting a dice and plateform from camels’s saddles. When every body has assembled even those called back. Prophet stands up and asked, "Do I have any right on you?" People shouted in in one voice, "You are the master and our Mowla"Hearing this, Prophet said, "I have been asked by Allah to deliver the command just received in” After praising Allah and Thine glories and mercies, he asked Ali to rise and come forward to the dice, held Ali’s arms and raised it up at over his head so high that armpit of Ali was visible and said, "Ali is the Mola “The Leader” of every body and every one who so ever takes Mohammad as a “A Leader” and in the “Same Contest”.

من  كنت  مولى  فهذا  علي مولى            

There was a great hue and cry every body congratulates and felicitates Ali for his exhalation. Even Omar comes forward and congratulates Ali “Ali, you have become Mowla of all momneen”     بخ بخ يا علي أنت مولى كل أ للمؤمنين  

Was this incidence at Khum i Ghadeer (Water-Well at Ghadeer) just a simple announcement or had some purpose. Was this declaration just out of love for a Cousin Brother or a Son-in-Law, if so, surely Prophet would have waited to reach Medina and would have declared this decree at his convenience and leisure either at usual after prayers talks or at the most during a Juma Prayer's address. Why Prophet had to call back all persons departed to their homes after the great Last sermon of Prophet at a gathering of 114.000 people. It clearly shows the importance of the message, under the command of Allah, Prophet wanted that every Muslim must hear this message, accept it (Compulsory by decree) and act upon it. Was this announcement just a sudden spurt and flight of an idea. If one carefully and minutely follows the history of Islam from its very emergence and inception,  one will come accross the first instructions of Allah to Prophet about the propagation and abdication of Islam. It was third years after the advent of Islam, Allah commands Mohammad, O! Prophet, 

 "وَأَنذِرْ عَشِيرَتَكَ الْأَقْرَبِينَ"

And warn your nearest relations.  Sura Al-Shuhra Aya 214 Ch: XIX

Mohammad being from Bani Hashim, he invited all adults members of Bani Hashim, his uncles (Abu Talib, Abbas, Hamza, Harith and AbuLahab) and cousins, in all 40, at the house of his uncle AbuTalib. Ali was assigned the duty to arrange for the dinner. Prophet gave him a hind limb of a lamb,  a bag of floor, and oil for cooking. The invitees were served with meal, the food suffized the guests and enough was left over. Prophet started the address, but abuLahab made mess of the address, it was intruped by his noise and yellings. Next day  they were again invited, food was prepared, served and during the address AbuLahab again disturbed the speech and gathering dispersed. Invitation was extended even on the third day, after the dinner, Mohammad stood up and started with name of Allah, in the audiance, AbuLahab gestured to stand up, Abu Talib, couldn't control his displeasure and annoyance, he pulled out his sword, and yelled, "sit down and shut up, you are the miscief monger, and have distrupted the address for two consecutive days, now sit quite and Listen to my Nephew patiently, other wise I will chop your head off" AbuLahab was stunned, he obeyed, sat down and listened. Mohammad said, "O! Sons of Abdul Matalib; Surely I am Messenger of Allah, There is Only one Allah, Alone Allah is to be worshipped. Allah has forbidden Idoltary. Stop worshipping Lat, Mannat, Azza, Hubal and other idols" Is there any body from among you, who testifies and seconds me, who will help and assist me in carrying out this duty and be my deputy and my successor. This was repeated thrice. None else than Ali stood up. Ali said, "Although I am only 13, apparantly lean and weak. But I bear witness, "Allah is one and alone he is to be worshipped, you are messenger of Allah and here by I promise to stand with you through thick and thin, at day and at night, during war and peace. I will help you with all my might, with my blood, my body and all my resources". Ali  repeated this thrice. Prophet said to Bani Hashim, “ Listen, remember and be witness, "Ali is my brother, my legatee, and my successor (khalifah) over you, so listen to him and obey him.” The men stood and while laughing told Abu Talib father of Ali, “Your nephew has ordered you to listen to your son and obey him.

History is witness to the truth of Ali's commitment. Whether it was Battle of Badr, Uhad, Ahzab, Khybar, Hunnain or Battle of Chains, when every body fled, deserted Prophet in the middle of the battle or remained silent and behaved like deaf and dumb on challange to fight. They questioned, argued, resented, doubted and disobeyed the decisions of Prophet. Ali obeyed and followed Prophet with out any hesitation or resentment. Ali was firm like a rock, he was like pole star in shear darkness. That declaration at Dinner for Kiths and kindreds was later authenticated on Day of Ghadeer, Day of Ghadeer was continuation of feat of Kiths and kindreds.

Ruh al-Ma'ani, Vol. 19, 122; al-Tantawi, Tafsir al-Jawahir, Vol. 13, 103; al-Hakim al-Naysaburi, al-Mustadrak ‘ala al-Sahihayn, Vol. 3, 135. Other historical sources, such as Sirat al-Halabi, say that the Prophet added, “And he will be my minister (wazir) and inheritor (warith).”
Ihqaq al-Haqq, Vol. 4, 62; Tarikh al-Tabari, Vol. 2, 117; Musnad Ahmad ibn Hanbal, Vol. 1, 159; Tarikh Abul Fida, Vol. 1, 116; Nadhm Durar al-Simtayn, 82; Kifayat al-Talib, 205; Tarikh Madinat Dimishq, Vol.1, Hadith 87, 139 and 143; al-Hasakani, Shawahid al-Tanzil, Vol. 1, 420; Muhammad ibn Jarir al-Tabari, Jami‘ al-Bayan, Vol. 19, 131; Jalal al-Din al-Suyuti, al-Durr al-Manthur, Vol. 5, 97; Tafsir ibn Kathir, Vol. 3, 350; al-Baghdadi, Tafsir al-Khazin, Vol. 3, 371; al-Alusi al-Baghdadi,