Each of the Messengers of God appearing prior to the Advent of Islam (including Prophet Muhammad Himself) had particular titles. I will offer a few such examples from the Qur'an and the Gospels for consideration:
The Christian Scriptures' characterized Jesus as "IBN'U'LLAH" or the Son of God, where God is depicted as the Heavenly Father. Such a characterization is a rather interesting one if one is to divorce oneself from the dogmatic interpretation of various Churches which have historically understood this "Sonhood" in a literal sense, implicating incarnation of God in the person of Jesus which is clearly rejected by the Qur'an.
NOTE: if the term "Son of God" was to be understood in the same spiritual sense as Jews being "sons of God" then there would have been no theological contradiction between the Qur'an and Christian dogma. I am making a distinction here between the teachings of Jesus as reflected in the Gospels and Churches' understanding of those teachings (i.e. dogma) which the Qur'an rejects.
4- Muhammad was RASOOL'U'LLAH the Messenger of God and Khatm'un'Nabieen
the Seal of the Prophets, Khatam'ur'Rosoleen, the Seal of the Messengers.
The term MESSENGER implies a DISTANT implement separating humanity from the Lord. Prophet Muhammad identifies Abraham, Moses, Jesus and other Personalities Who have appeared throughout the history as "Messengers of God".
This brings us to the Dispensation of The Bab. It is interesting to note in this context that The Bab began to use a new terminology "mazhar-i Amr'u'llah" or the "Manifestation of the Cause or Command of God", or in short "Manifestation of God" to characterize the Revelator of God's Will, Command and Grace as opposed to "nabi" ("Prophet") or "rasool" ("Messenger"). Moreover, The Bab took the Biblical title "the Gate" for Himself and He associated the Biblical title of "Glory of God" (i.e. the meaning of the Arabic term Baha'u'llah) with the Personage Whom He said would appear immediately after the end of His own dispensation.
The following verse of the Bible demonstrates what The Bab had in mind: "And the GLORY OF THE LORD came into the house by the way of the GATE whose prospect is toward the EAST." [Ezekiel 43:4]. Also; "And behold, the glory of the God of Israel came from the way of the EAST." [Ezekiel 43:2]
5- In the revelations that the Bab received from God, the various terms referring to the soon to appear Promised One--- The Bab, or Mahdi, or Qa'im, or the Return of Elijah, or the Return of John the Baptist--- were all identified as BAB'U'LLAH or the "Gate of God"
"O Qurratu'l-Ayn! [literally Solace of the Eyes. Here God is addressing the Bab.-KH] Say: Verily I am the `Gate of God' and I give you to drink, by the leave of God, the sovereign Truth, of the crystal-pure waters of His Revelation which are gushing out from the incorruptible Fountain situate upon the Holy Mount. And those who earnestly strive after the One True God, let them then strive to attain this Gate [The Bab is referring to Qur'an 83:25-26 here.-KH] Verily God is potent over all things." Qayyum'ul-Asma', Chapter 24
6- The Founder of the Baha'i Faith, Baha'u'llah (the Glory of God), claimed to be the Return of Christ. This appellation implies God being manifested to humanity in the full virtue of His light, glory and splendor. That is to say, this is the Day when God will appear in the most clear sense.
The terms GLORY or LIGHT imply the POSSIBILITY of VISION (i.e. presence)-- and are the strongest means in the depiction of the Lord.
Neither The Bab nor Baha'u'llah identified Themselves as "nabi" ("Prophet") to humanity. Similarly, neither The Bab nor Baha'u'llah identified themselves as "Rasool" (Apostle of God) to humanity. They both refrained from doing so because both Muslims and Christians were warned against accepting anyone who was to appear by either of these titles. The following quotes help clarify this issue:
(4) earthquakes will increase in number
(6) afflictions will appear,
(8) till wealth will be in abundance ---- so abundant that a wealthy person will worry lest nobody should accept his Zakat, and whenever he will present it to someone, that person (to whom it will be offered) will say, 'I am not in need of it,
(11) and till the sun rises from the West. So when the sun will rise and the people will see it (rising from the West) they will all believe (embrace Islam) but that will be the time when: (As Allah said,) 'No good will it do to a soul to believe then, if it believed not before, nor earned good (by deeds of righteousness) through its Faith.' (6.158)
And the Hour will be established while two men spreading a garment in front of them but they will not be able to sell it, nor fold it up; and the Hour will be established when a man has milked his she-camel and has taken away the milk but he will not be able to drink it; and the Hour will be established before a man repairing a tank (for his livestock) is able to water (his animals) in it; and the Hour will be established when a person has raised a morsel (of food) to his mouth but will not be able to eat it." Sahih Bukhari 9:237
D- The claim of the Promised Mahdi and the Returned Christ must be "Lordship" (i.e. They must address people by saying: "ana rabbokom" or "I am your Lord"). This will be discussed later on. They must not claim "ana nabiakom" (i.e. prophethood) or "ana rasoolokom" (i.e. apostleship). This is a very unique and clear sign to distinguish between true and false.
The concept of the "Seal of the Prophets" (mentioned in the Qur'an) and "Seal of the Apostles" (mentioned in the Ahadith... i.e. Muslim oral traditions) are the key to understanding the following warnings of Jesus Christ (which are entirely consistent with the above mentioned Hadith [Bukhari 9:237].)
Jesus said: "Then if any man shall say unto you, Lo, here is Christ, or there; believe it not, for there shall arise false Christs and false prophets, and show great signs and wonders; insomuch that, if it were possible, they should deceive the very elect. Behold I have told you before[hand]." Matthew 24:23-25
"Beware of false prophets, which come to you in sheep's clothing, but inwardly they are ravening wolves. Ye shall know them by their fruits. Do men gather grapes of thorns, or figs of thistles? Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit. A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit. Wherefore by their fruits ye shall know them." Matthew: 7:15-20