Paraclete comes from the Koine Greek word παράκλητος (paráklētos). A combination of "para" (beside/alongside) and "kalein" (to call), the word first appears in the Bible in John 14:16. John Muddiman and John Barton further explain the development of the meaning of this term;
The word parakletos is a verbal adjective, often used of one called to help in a lawcourt. In the Jewish tradition the word was transcribed with Hebrew letters and used for angels, prophets, and the just as advocates before God's court. The word also acquired the meaning of'one who consoles' (cf. Job 16:2, Theodotion's and Aquila's translations; the LXX has the correct word parakletores). It is probably wrong to explain the Johannine parakletos on the basis of only one religious background. The word is filled with a complex meaning: the Spirit replaces Jesus, is an advocate and a witness, but also consoles the disciples.
In Classical GreekEdit
Citizens of Athens, I do not doubt that you are all pretty well aware that this trial has been the center of keen partisanship and active canvassing, for you saw the people who were accosting and annoying you just now at the casting of lots. But I have to make a request which ought to be granted without asking, that you will all give less weight to private entreaty or personal influence than to the spirit of justice and to the oath which you severally swore when you entered that box. You will reflect that justice and the oath concern yourselves and the commonwealth, whereas the importunity and party spirit of advocates serve the end of those private ambitions which you are convened by the laws to thwart, not to encourage for the advantage of evil-doers.— Demosthenes, On the False Embassy 19:1
Philo speaks several times of "paraclete" advocates primarily in the sense of human intercessors.
The word is not used in the Septuagint, the word "comforters" being different in Job. Other words are used to translate the Hebrew word מְנַחֵם (mənaḥḥēm "comforter") and מליץ יושר (Melitz Yosher).
In the Greek New Testament the word is most prominent in the Johannine writings. It appears in the Gospel of John where it may be translated into English as "counselor", "helper", “advocate”, or "comforter".
The New Testament Studies, a peer-reviewed academic journal published by Cambridge University Press, describes a "striking similarity" between the defined attributes of what the Paraclete is, and is to do, and what the outcome of Christian prophecy has spoken to, explaining the Paraclete as the post-Passover gift of the Holy Spirit. "The Paraclete represents the Spirit as manifested in a particular way, as a pneumatic Christian speech charisma. Every verb describing the ministry of the Paraclete is directly related to his speech function."
During his period as a hermit in the mid-12th century, Peter Abelard dedicated his chapel to the Paraclete because "I had come there as a fugitive and, in the depths of my despair, was granted some comfort by the grace of God."
Raymond Brown (1970), supported by George Johnston (2005), also says that the "another Paraclete" of John 14:16 is in many ways another Jesus, the presence of Jesus after Jesus ascends to his Father.
The Gospel of Matthew twice uses the passive form of the corresponding verb παρακαλῶ, in 2:18 and 5:4. In both instances, the context is of mourning, and the meaning of the verb is "to be comforted".
Paraclete first appearing in gospelEdit
Here is the context of the passage in John 14:15-14:27 with the translation of Paraclete as Advocate shown in bold:
15 “If you love me, keep my commands. 16 And I will ask the Father, and he will give you another Advocate to help you and be with you forever— 17 the Spirit of truth. The world cannot accept him, because it neither sees him nor knows him. But you know him, for he lives with you and will be in you. 18 I will not leave you as orphans; I will come to you. 19 Before long, the world will not see me anymore, but you will see me. Because I live, you also will live. 20 On that day you will realize that I am in my Father, and you are in me, and I am in you. 21 Whoever has my commands and keeps them is the one who loves me. The one who loves me will be loved by my Father, and I too will love them and show myself to them.”
22 Then Judas (not Judas Iscariot) said, “But, Lord, why do you intend to show yourself to us and not to the world?”
23 Jesus replied, “Anyone who loves me will obey my teaching. My Father will love them, and we will come to them and make our home with them. 24 Anyone who does not love me will not obey my teaching. These words you hear are not my own; they belong to the Father who sent me.
25 “All this I have spoken while still with you. 26 But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you all things and will remind you of everything I have said to you. 27 Peace I leave with you; my peace I give you. I do not give to you as the world gives. Do not let your hearts be troubled and do not be afraid.
Many Muslim writers have argued that “another Paraclete” (John 14:16)—the first being Jesus—refers to Muhammad. This claim is based on the Quran verse from Surah 61 verse 6. The earliest scholar to argue this case is probably Ibn Ishaq (died 767), who Islamic tradition states was the grandson of a Christian. Others who interpreted the paraclete as a reference to Muhammad include Ibn Taymiyyah, Ibn Kathir, Al-Qurtubi, Rahmatullah Kairanawi (1818–1891), and contemporary Muslim scholars such as Martin Lings.
Here is a translation of the passage in Surat 61 verse 6:
And [mention] when Jesus, the son of Mary, said, "O children of Israel, indeed I am the messenger of Allah to you confirming what came before me of the Torah and bringing good tidings of a messenger to come after me, whose name is Ahmad." But when he came to them with clear evidences, they said, "This is obvious magic.— Sahih International
"Coming back to the term "Ahmad", Muslims have suggested that Ahmad is the translation of periklutos, celebrated or the Praised One, which is a corruption of parakletos, the Paraclete of John XIV, XV and XVI."
A few Muslim commentators, such as David Benjamin Keldani (1928), have argued the theory that the original Greek word used was periklytos, meaning famed, illustrious, or praiseworthy, rendered in Arabic as Ahmad (another name of Muhammad), and that this was substituted by Christians with parakletos. However, there is not one Greek manuscript in existence with this reading, all Greek manuscripts read παράκλητος parakletos.
Regarding what the original Greek term was, according to A. Guthrie and E. F. F. Bishop:
"Early translators knew nothing about the surmised reading of periklutos for parakletos, and its possible rendering as Ahmad …. Periklutos does not come into the picture as far as Ibn Ishaq and Ibn Hisham are concerned. The deception is not theirs. The opportunity to introduce Ahmad was not accepted—though it is highly improbable that they were aware of it being a possible rendering of Periklutos. It would have clinched the argument to have followed the Johannine references with a Quranic quotation.”
"Once more, if we omit the phrase, ‘bearing the name Ahmad,’ and regard Muhammad as still drawing lessons from previous history, the dubious passage might refer to what happened at Pentecost, and other incidents recorded in the earlier chapters of the Acts. With the absence of any claim on this passage either by Ibn Ishaq or Ibn Hisham, may we go further and suggest that the two Arabic words rendered by Dr. Bell, ‘bearing the name Ahmad,’ are an interpolation to be dated after the death of Muhammad.” (emphasis in original)
A letter from antiquityEdit
“We recognize Matthew, Mark, Luke, and John as the authors of the Gospel, and yet I know that this truth, recognized by us Christians wounds you, so that you seek to find accomplices for your lie. In brief, you admit that we say that it was written by God, and brought down from the heavens, as you pretend for your Furqan, although we know that it was `Umar, Abu Turab and Salman the Persian, who composed that, even though the rumor has got round among you that God sent it down from heavens…. [God] has chosen the way of sending [the human race] Prophets, and it is for this reason that the Lord, having finished all those things that He had decided on beforehand, and having fore-announced His incarnation by way of His prophets, yet knowing that men still had need of assistance from God, promised to send the Holy Spirit, under the name of Paraclete, (Consoler), to console them in the distress and sorrow they felt at the departure of their Lord and Master. I reiterate, that it was for this cause alone that Jesus called the Holy Spirit the Paraclete, since He sought to console His disciples for His departure, and recall to them all that he had said, all that He had done before their eyes, all that they were called to propagate throughout the world by their witness. Paraclete thus signifies "consoler", while Muhammad means "to give thanks", or "to give grace", a meaning which has no connection whatever with the word Paraclete.” 
- "Paraclete | Origin and meaning of paraclete by Online Etymology Dictionary".
- Barton, John, and John Muddiman, eds. The Oxford Bible Commentary. Oxford University Press, 2007, 987.
- According to Walter Bauer's Greek-English Lexicon of the New Testament and Other Early Christian Literature: "the technical meaning 'lawyer', 'attorney' is rare."
- παρά-κλητος, ον, A. called to one's aid, in a court of justice : as Subst., legal assistant, advocate, D.19.1, Lycurg. Fr.102, etc. 2. summoned, “δοῦλοι” D.C.46.20, cf. BGU601.12 (ii A.D.). II. intercessor, Ph.2.520 : hence in NT, Παράκλητος, of the Holy Spirit, Ev.Jo.14.16, cf. 1 Ep.Jo.2.1.
- For a summary of rabbinical usage see Jewish Encyclopedia 1914 "Paraclete"
- The Orthodox Jewish Brit Chadasha Bible Translation
- Definition and etymology of Paraclete
- "The Influence of Christian Prophecy on the Johannine Portrayal of the Paraclete and Jesus". New Testament Studies. 25 (1): 113–123. October 1978. Retrieved 27 May 2016.
- Allison, Gregg (2011). Historical Theology: An Introduction to Christian Doctrine. Zondervan. p. 431. ISBN 9780310410416. Retrieved 25 September 2014.
- "The Letters of Abelard and Heloise", Betty Radice, Trans. London: Penguin, 1973. P. 30
- Lutkemeyer, Lawrence J. (1946). "THE ROLE OF THE PARACLETE (Jn. 16:7-15)". The Catholic Biblical Quarterly. 8 (2): 220–229. JSTOR 43719890.
- Brown, Raymond Edward, ed. The gospel according to John. Vol. 29. Cambridge University Press, 1970, 1141. Brown writes; "Thus, the one whom John calls "another Paraclete" is another Jesus. Since the Paraclete can come only when Jesus departs, the Paraclete is the presence of Jesus when Jesus is absent. Jesus' promises to dwell within his disciples are"
- Kinn, James W. The Spirit of Jesus in Scripture and prayer. Rowman & Littlefield, 2004, 60. Winn writes; "Second, the whole complex of parallels above leads Raymond Brown to a more profound conclusion: the Holy Spirit continues the presence of Jesus. Thus the one whom Jesus calls "another Paraclete" is in many ways another Jesus, ."
- Johnston, George. The spirit-paraclete in the gospel of John. Vol. 12. Cambridge University Press, 2005, 94. Johnston writes; "Brown cannot regard such parallelism as coincidental, and he is perfectly correct. His conclusion is that 'as "another Paraclete" the Paraclete is, as it were, another Jesus ... and the Paraclete is the presence of Jesus when Jesus is "
- Marthaler, Berard L. The creed: The apostolic faith in contemporary theology. Twenty-Third Publications, 1993, 275. Marthaler writes; "Thus," writes Brown, "the one whom John calls 'another Paraclete' is another Jesus."17 The Paraclete is the presence of God in the world when Jesus ascends to the Father."
- Greek Word Study Tool (publisher=Perseus.tufts.edu): παρακαλέω, A, III, 2
- John 14:15-14:27
- Liddell and Scott's celebrated Greek-English Lexicon gives this definition for periklutos: "heard of all round, famous, renowned, Latin inclytus: of things, excellent, noble, glorious". Rev. James M. Whiton, ed. A Lexicon abridged from Liddell and Scott's Greek-English Lexicon. New York: American Book Company, N.D. c.1940s, p.549. Periklutos occurs in The Iliad and The Odyssey, and Hesiod's Theogony.
- Donzel, E. Van and B. Lewis, Ch. Pellat. "Isa" in Encyclopedia of Islam Volume 4, 1997, 83.
- Watt (1991) pp. 33–34
- Reuben J. Swanson, ed., New Testament Greek Manuscripts: John. William Carey International University Press, 1998. Variant Readings Arranged in Horizontal Lines Against Codex Vaticanus – see John 14:16, 26; 15:26; 16:7. Also see Nestle-Aland, eds., Novum Testamentum Graece, 28th ed. Stuttgart: Deutsche Biblegesellschaft, 2012.
- A. Guthrie and E. F. F. Bishop, p.253–254.
- Watt, W. Montgomery (April 1953). "His Name is Ahmad". The Muslim World. 43 (2): 110–117. doi:10.1111/j.1478-1913.1953.tb02180.x.
- A. Guthrie and E. F. F. Bishop, The Paraclete, Almunhamanna and Ahmad, Muslim World XLI (October, 1951), p.254–255; italics: emphasis in original.
- Hoyland, Robert G. Seeing Islam as others saw it: a survey and evaluation of Christian, Jewish and Zoroastrian writings on early Islam. Darwins Press, 1999, 499.
- Arthur Jeffery, Ghevond's Text of the Correspondence Between `Umar II and Leo III. Harvard Theological Review. XXXVII, 1944, 269–332.