If the Quran insists on the exalted position that God's messengers occupy in the history of revelation and calls on the Muslims to believe in the heavenly books that they brought, it is in order to confirm the truth and veracity of religion and to demonstrate that human beings must at all times turn to pure, authentic religions that derive from revelation, the religious guidance of humanity being entrusted by God in every age to a particular Prophet.

If we see any variation in the procedures and programs followed by the various Prophets, it is to be explained in terms of the swift changes that take place in human development and the passage of the human being from one stage to the next. For all the Prophets were, without distinction, true guides of humanity to the goals set by God; they preached a single doctrine deriving from a single source, advancing it in accordance with the dictates and circumstances of their time. The Quran says: "We make no distinction among any of the Prophets."(2:135)

The sending of the Prophets formed part of the plan of creation from the very beginning, and the chain of the Messengers represented the gradual unfolding of Divine guidance. Just as the human being advanced in the general conduct of his life, so, too, the mission of the Prophets moved forward, in harmony with the progress of the human being, and the Prophets accordingly foretold the appearance of the Prophets who would succeed them. 

The Prophet of Islam confirmed the messengerhood of previous Prophets and the heavenly books they had brought, just as they had confirmed the Prophets who had preceded them. Those earlier Prophets had also proclaimed that others would follow them, so that the very leaders of religion clearly proclaimed the interconnectedness of all true religion.

Although the fact that the appearance of a Prophet has been foretold cannot serve in itself as proof for the veracity of a person's claim to prophethood, it does serve to indicate what might be the nature of a true Prophet and what qualities might be observed in him.

Were a name to be specified when predicting the emergence of a Prophet, this would, of course, be open to misuse, since naming is a conventional matter and anyone could adopt the name in question.

Similarly, to specify the exact moment when the Prophet was to appear would have facilitated the task of false claimants by giving them the opportunity to prepare themselves for making their fateful and monstrous claim. Furthermore, this might have led to a profusion of claims, which would then have induced confusion in the minds of people.

It may not be difficult for people with the ability to examine matters carefully and realistically to tell the difference between a true Messenger of God and false and erroneous claimants. But at the same time, it should not be forgotten that recognizing the truth, particularly in circumstances where it is mixed with falsehood, is not easy for those many people whose level of thought and awareness is not especially high. Many are those who fall into traps laid by the ambitions of the wicked.

It is for these reasons that the characteristics of a future Prophet are spelled out, these being the distinctive signs by which he may be recognized. Then those scholars on whom others depend for guidance in this matter can measure the claimant to prophethood against the characteristics that have been mentioned, devoting themselves to the task in utter purity and sincerity. 

Christianity never advanced the claim that the religion of Jesus would be permanent and eternal or that Jesus was the Seal of the Prophets and a guarantor of the textual integrity of the Gospels.

Other religions also did not make analogous claims for themselves.

Islam does, however, speak of being the last and most perfect of all religions and of its Messenger being the Seal of the Prophets.

It therefore follows that the heavenly book of Islam must always be protected from corruption and distortion.

The fundamental difference between the sacred books of Christianity and Islam is that Christianity lacks a revealed text that was fixed at the very time of its origins, whereas Islam possesses one.

The Gospels which we now have at our disposal have been extensively criticized by scholars and researchers who have examined different copies of the Gospels and have reached the conclusion that the New Testament has undergone many changes. There are many indications that the text of the Gospels has been codified to a considerable extent, to conform to personal beliefs and opinions.

John Nass, a historian of religions, writes as follows: "The history of Christianity is the story of a religion that arose from a belief in Divine incarnation having taken place in the person of its founder. All the teachings of Christianity revolve around the conviction that the person of Jesus represents the clearest manifestation of the Divine essence. But this religion that started out with a belief in Divine incarnation was transformed through a series of developments and took on a human dimension so that all the weaknesses and imperfections of the human condition began to appear in it.

"The story of religion is extremely long, including many ups and downs and moments of both glory and shame; it is these contrasts that give it meaning and significance. In none of the world's religions have such exalted spiritual aims been manifest as in Christianity; but equally in none of them has the failure to reach those aims been so marked."

Despite the textual corruption to which the Gospels have been subject, there are indications that the expressions "Spirit of Truth," "Holy Ghost" and "Comforter' which they contain may refer to the Prophet of Islam.

The Gospels record that Jesus addressed his disciples as follows: "Hereafter I will not talk much with you: for the prince of this world cometh, and hath nothing in me.[52] But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of truth, which proceedeth from the Father, he shall testify of me."[53] "Nevertheless, I tell you the truth: It is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you. And when he is come, he will reprove the world of sin, and of righteousness and of judgment: of sin, because they believe not on me; of righteousness because I go to my Father, and you see me no more; of judgment because the prince of this world is judged. I have yet many things to say unto you but ye cannot bear them now. How be it, when he, the Spirit of truth is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak; and he will show you things to come. He shall glorify me, for he shall receive of mine and shall show it unto you."[54] "But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you."[55]

If we say that the Comforter is identical with the Holy Ghost, we know that the Holy Ghost constantly accompanied Jesus and it would therefore not have been correct for him to say: "He will not come to you until I go."

When the Prophet Jesus says, "The prince of the world cometh" and that he will guide mankind, he is in effect accepting the religion to be brought by that person as the most perfect of all religions. Can the description of him given by Jesus fit anyone other than Muhammad, upon whom be peace and blessings?

When Jesus says, "He shall testify of me," and "he shall glorify me," did anyone other than the Prophet of Islam revere and honor Jesus or defend the innocence of Mary against the unworthy accusations made by the Jews?

Was it the Holy Ghost that did these things, or the Prophet of Islam? In addition to the fact that these verses clearly bear witness that the Comforter, the Holy Ghost, the Spirit of truth, cannot be anyone other than the Prophet of Islam, we also encounter the world "Paraclete" in some of the Gospels, the meaning of which is identical with that of the named Muhammad and Ahmad. Translators of the Gospels however have taken the work perikletos, a proper name in Greek equivalent in its meaning to Ahmad, to be parakletos, translating this as "Comforter." 

Dr. Bucaille has a valuable discussion of this subject in the Chapter called "Jesus's Last Dialogues. The Paraclete of John's Gospel." "John is the only evangelist to report the episode of the last dialogue with the Apostles. It takes place at the end of the Last Supper and before Jesus's arrest. It ends in a very long speech: four chapters in John's Gospel (14 to 17) are devoted to this narration which is not mentioned anywhere in the other Gospels. These chapters of John nevertheless deal with questions of prime importance and fundamental significance to the future outlook. They are set out with all the grandeur and solemnity that characterizes the farewell scene between the Master and His disciples.

"This very touching farewell scene which contains Jesus's spiritual testament is entirely absent from Matthew, Mark and Luke. How can the absence of this description be explained? One might ask the following: did the text initially exist in the first three Gospels? Was it subsequently suppressed? Why? It must be state immediately that no answer can be found; the mystery surrounding this huge gap in the narrations of the first three evangelists remains as obscure as ever.

"The dominating feature of this narration - seen in the crowning speech - is the view of man's future that Jesus describes, His care in addressing His disciples and through them the whole of humanity, His recommendations and commandments and His concern to specify the guide whom man must follow after His departure. The text of John's Gospel is the only one to designate him as parakletos in Greek which in English has become Paraclete. 

The following are the essential passages:

"If you love me, you will keep my commandments. And I will pray the Father, and he will give you another Paraclete." (14, 15-16)

"What does 'Paraclete' mean? The present text of John's Gospel explains its meaning as follow:

"But the Paraclete, the Holy Spirit, whom the Father will send in my name, he will teach you all things, and bring to your remembrance all that I have said to you." (14, 26).

"...he will bear witness to me..." (15, 26)

"It is to your advantage that I go away, for if I do not go away, the Paraclete will not come to you; but if I go, I will send him to you.

And when he comes, he will convince the world of sin and of righteousness and of judgment..." (16, 74)

"When the Spirit of truth comes, he will guide you into all the truth; for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come. He will glorify me..." (16,13-14). 

"(It must be noted that the passages in John, chapters 14-17, which have not been cited here, in no way alter the general meaning of these quotations).

On a cursory reading, the text which identifies the Greek work 'Paraclete' with the Holy Spirit is unlikely to attract much attention.

This is especially true when the subtitles of the text are generally used for translations and the terminology commentators employ in works for mass publication direct the reader towards the meaning in these passages that an exemplary orthodoxy would like them to have. Should one have the slightest difficulty in comprehension, there are many explanations available such as those given by A. Tricot in his Little Dictionary of the New Testament (Petit Dictionnaire du Nouveau Testament) to enlighten one on this subject. In his entry on the Paraclete this commentator writes the following:

" 'This name or title translated from the Greek is only used in the New Testament by John: he uses it four times in his account of Jesus's speech after the Last Supper 56 (14, 16 and 26; 15, 26; 16, 7) and once in his First Letter (2, 1). In John's Gospel the word is applied to the Holy Spirit; in the Letter it refers to Christ. "Paraclete" was a term in current usage among the Hellenist Jews, First century AD, meaning "intercessor," "defender" (...) Jesus predicts that the Spirit will be sent by the Father and Son. Its mission will be to take the place of the Son in the role he played during his mortal life as a helper for the benefit of his disciplines. The Spirit will intervene and act as a substitute for Christ, adopting the role of Paraclete or omnipotent intercessor.'

"This commentary therefore makes the Holy Spirit into the ultimate guide of man after Jesus's departure. How does it square with John's text?

"It is a necessary question because a priori it seems strange to ascribe the last paragraph quoted above to the Holy Spirit: 'for he will not speak on his own authority, but whatever he hears he will speak, and he will declare to you the things that are to come.' It seems inconceivable that one could ascribe to the Holy Spirit the ability to speak and declare whatever he hears...Logic demands that this question be raised, but to my knowledge, it is not usually the subject of commentaries. 

"To gain an exact idea of the problem, one has to go back to the basic Greek text. This is especially important because John is universally recognized to have written in Greek instead of another language. The Greek text consulted was the Norum Testamentum Graece.[57]

"Any serious textual criticism begins with a search for variations. Here it would seem that in all the known manuscripts of John's Gospel, the only variation likely to change the meaning of the sentence is in passage 14, 26 of the famous Palimpsest version written in Syriac.[58] Here it is not the Holy Spirit that is mentioned, but quite simply the Spirit. Did the scribe merely miss out a word or, knowing full well that the text he was to copy claimed to make the Holy Spirit hear and speak, did he perhaps lack the audacity to write something that seemed absurd to him? Apart from this observation there is little need to labor the other variations, they are grammatical and do not change the general meaning. The important thing is that what has been demonstrated here with regard to the exact meaning of the verbs 'to hear' and 'to speak' should apply to all the other manuscripts of John's Gospel, as is indeed the case.

The verb 'to speak' in the translation is the Greek verb 'laleo' which has the general meaning of 'to emit sounds' and the specific meaning of 'to speak'. This verb occurs very frequently in the Greek text of the Gospels. It designates a solemn declaration made by Jesus during His preachings. It therefore becomes clear that the communication to man which He here proclaims does not in any way consist of a statement inspired by the agency of the Holy Spirit.

It has a very obvious material character moreover, which comes from the idea of the emission of sounds conveyed by the Greek word that defines it.

"The two Greek verbs 'akouo' and 'laleo' therefore define concrete actions which can only be applied to a being with hearing and speech organs. It is consequently impossible to apply them to the Holy Spirit.

"For this reason, the text of this passage from John's Gospel, as handed down to us in Greek manuscripts, is quite incomprehensible if one takes it as a whole, including the words 'Holy Spirit' in passage 14, 26: "But the Paraclete, the Holy Spirit, whom the Father will send in my name" etc. It is the only passage in John's Gospel that identifies the Paraclete with the Holy Spirit.

"If the words 'Holy Spirit" (to pneuma to agton) are omitted from the passage, the complete text of John then conveys a meaning which is perfectly clear. It is confirmed moreover, by another text by the same evangelist, the First Letter, where John uses the same word 'Paraclete' simply to mean Jesus, the intercessor at God's side.59 According to John, when Jesus says (14, 16): 'And I pray the Father, and he will give you another Paraclete,' what He is saying is that 'another intercessor will be sent to man, as He Himself was at God's side on man's behalf during His earthly life.

"According to the rules of logic therefore, one is brought to see in John's Paraclete a human being like Jesus, possessing the faculties of hearing and speech formally implied in John's Greek text.

Jesus therefore predicts that God will later send a human being to Earth to take up the role defined by John, i.e. to be a prophet who hears God's word and repeats his message to man. This is the logical interpretation of John's texts arrived at if one attributes to the words their proper meaning.

"The presence of the term 'Holy Spirit' in today's text could easily have come from a later addition made quite deliberately. It may have been intended to change the original meaning which predicted the advent of a prophet subsequent to Jesus and was therefore in contradiction with the teachings of the Christian churches at the time of their formation; these teachings maintained that Jesus was the last of the prophets."[60]

The Grande Encyclopedie Francaise has the following to say in its entry on Muhammad, upon whom be blessings and peace: "Muhammad, the founder of the religion of Islam, the Messenger of God and the Seal of the Prophets. The word Muhammad means the one who is praised; it is derived from the root hamd, meaning laudation and veneration. By a remarkable coincidence, there is another name, derived from the same root as Muhammad and synonymous with it, Ahmad, which was very probably used by the Christians of Arabia as the equivalent of Paraclete. Ahmad, meaning much praised and revered, is the translation of the word perikletos which has been mistakenly rendered as parakletos. For this reason, Muslim religious writers have repeatedly remarked that this name refers to the future appearance of the Prophet of Islam. The Quran refers to this matter in a remarkable verse in Surah Saff."[61] 

The verse referred to by the encyclopedia runs as follows: "When Jesus son of Mary said to the Children of Israel, 'I am God's Messenger sent unto you. I confirm the veracity of the Torah which is here in front of me and give you glad tidings that a Prophet will come after me whose name is Ahmad.' But when the Prophet came to the people with proofs and miracles, they said, 'This is clear magic.' "(61:6)

In another verse the Quran says the following: "Those Jews and Christians will enjoy God's mercy who follow the unlettered Prophet whose description they read in the Torah and the Gospels. He is a Prophet who summons them unto good and restrains them from evil, who makes the pure licit for them and the impure illicit, and releases them from the shackles of heavy and arduous obligations. So those who believe in him, revere him and aid him, and follow his clear and luminous guidance, are in truth on the path of salvation."(6:156)