In the second sermon of the Nahj al-Balāghah, Imam ‘Ali (‘a) first speaks in regards to the foundations of monotheism (Tawḥīd) and then he goes on to speak in regards to the issue of prophethood. He says the following: “I give witness that Muhammad (saww) is his servant and messenger”. What is interesting to note here is that before he is introduced as a messenger, he is first introduced as God’s servant and slave.
In the second sermon of the Nahj al-Balāghah, Imam ‘Ali (‘a) first speaks in regards to the foundations of monotheism (Tawḥīd) and then he goes on to speak in regards to the issue of prophethood. He says the following: “I give witness that Muhammad (saww) is his servant and messenger”. What is interesting to note here is that before he is introduced as a messenger, he is first introduced as God’s servant and slave. It can be said that if one is not a slave of God, then he cannot be his messenger. Some people have raised the prophets so high as to make them in to divine figures and this is while the highest honor that the prophets had was in their servanthood in front of God.
Imam ‘Ali (‘a) has then continued and described the prophethood of Muhammad (saww) in the following words: “Allah sent him with the illustrious religion, effective emblem, written Book, effulgent light, sparkling gleam and decisive injunction in order to dispel doubts…” There are numerous commentaries as to what these six des c r i p tions are referring to. The first term mentioned (the illustrious religion) is a reference to Islam, while the second term is a reference to the miracles that took place. The third term is a reference to the Holy Quran and the fourth is a reference to the divine knowledge that the Prophet (saww) possessed. The fifth is a reference to the Sunnah of the Prophet (saww) and the sixth term is a reference to the verse of the Quran which says: “So proclaim what you have been commanded, and turn away from the polytheists”, which is a statement for stopping dissimulation and expressing the unique oneness of God in front of the polytheists and enemies of Islam. The possibility also exists that the fourth and fifth terms are more detailed explanations on the nature of the Quran, for the Quran is a means of giving enlightenment to various thoughts and upon the human society as a whole.
Then Imam ‘Ali (‘a) speaks in regards to the ultimate goal behind the message of the Prophet (saww), as well as the reasons behind the revelation of the Quran, the miracles that ensued, and the rules and code of law that Islam possesses. He says:
لِلشُّبُهاتِ، وَ احْتِجاجاً بِالْبَیِّناتِ، وَ تَحْذیراً بِالآیاتِ وَ تَخْویفاً بِالمَثُلات اِزاحَةً
The goal of the Bi’thah and what the Prophet (saww) was sent down with can be found in several things. One reason was that he could remove ‘the doubts that had come in to place and use clear and concise logic and reasoning. Through the use of divine signs, he could warn people of disobedience to God and frighten them of the punishments that such disobedience would entail.’
In the commentary of these aforementioned four terms, it can be said that the first of them (Izāḥa’ Lilshubuhāt) is a reference to the realities that are made apparent and clear in light of the divine proof that is given to human kind and which completely destroys all possible doubt and questions that were previously present. The second term (Wa Iḥtijājan Bilbayyināt) is a reference to the evident miracles which were presented before some of the people who were not satisfied with the rational evidences of the Prophet (saww); these miracles made the religion of Islam a certainty for these people and brought them within its fold. The third term (Taḥdhīr Bihī Āyāt) is a warning of the punishments that are to come in the hereafter and the fourth term (Takhwīf Bihī Muthillāt) is a warning of the punishments that will come in this world. This fourth category has been mentioned in the following Quranic verse:
وَیَسْتَعْجِلُونَکَ بِالسَّیِئَةِ قَبْلَ الْحَسَنَةِ وَ قَدْ خَلَتْ مَنْ قَبْلِهِمُ الْمَثُلات
“They would press you for evil sooner than for good, though there have already gone by before them exemplary punishments….”
 The term Ma'thūr is from the root word Athar which means a sign or indication which has been left from something. It is for this same reason that the ancient sciences are called 'Ilm al-Ma'thūr.  The term Sāṭi' comes from the root word Suṭū' which means to announce and to spread. It also means for something to grow tall or be elevated. Therefore, the terms Nūr Sāṭi' means a very widespread and long reaching light.  Ṣādi' comes from the root word Ṣada' which means to create a split upon something that is very solid and firm; it is used to refer to something very decisive and sure.  Surah Ḥijr, verse 94.  IzāḥahÞ comes from the root word Zayḥ (based on the root weight Zayd) and it contains the meaning of going far from something. Due to this reason, the term Izāḥah is used to mean taking it far.  Muthillāt is the plural form of Muthul and it means a calamity or some form of distress which envelops an individual and is then used as a warning and lesson for other people.  Surah Ra'ad, verse 6.  Payāme Imām 'Ali ('a), vol. 1, p. 279.