Who is Baha'u'llah?

Baha'is recognize Baha'u'llah "as the Judge, the Lawgiver and Redeemer of all mankind,
as the Organizer of the entire planet,
as the Unifier of the children of men,
as the Inaugurator of the long-awaited millennium,
as the Originator of a new "Universal Cycle,"
as the Establisher of the Most Great Peace,
as the Fountain of the Most Great Justice,
as the Proclaimer of the coming of age of the entire human race,
as the Creator of a new World Order,
and as the Inspirer and Founder of a world civilization.

To Israel He was neither more nor less than the incarnation of the "Everlasting Father,"
the "Lord of Hosts" come down "with ten thousands of saints";
to Christendom Christ returned "in the glory of the Father,"
to Shi'ah Islam the return of the Imam Husayn;
to Sunni Islam the descent of the "Spirit of God" (Jesus Christ);
to the Zoroastrians the promised Shah-Bahram;
to the Hindus the reincarnation of Krishna;
to the Buddhists the fifth Buddha.

In the name He bore He combined those of the Imam Husayn, the most illustrious of the successors of the Apostle of God - the brightest "star" shining in the "crown" mentioned in the Revelation of St. John - and of the Imam Ali, the Commander of the Faithful, the second of the two "witnesses" extolled in that same Book. He was formally designated Baha'u'llah, an appellation specifically recorded in the Persian Bayan, signifying at once the glory, the light and the splendor of God, and was styled the "Lord of Lords," the "Most Great Name," the "Ancient Beauty," the "Pen of the Most High," the "Hidden Name," the "Preserved Treasure," "He Whom God will make manifest," the "Most Great Light," the "All-Highest Horizon," the "Most Great Ocean," the "Supreme Heaven," the "Pre-Existent Root," the "Self-Subsistent," the "Day-Star of the Universe," the "Great Announcement," the "Speaker on Sinai," the "Sifter of Men," the "Wronged One of the World," the "Desire of the Nations," the "Lord of the Covenant," the "Tree beyond which there is no passing." He derived His descent, on the one hand, from Abraham (the Father of the Faithful) through his wife Katurah, and on the other from Zoroaster, as well as from Yazdigird, the last king of the Sasaniyan dynasty. He was moreover a descendant of Jesse, and belonged, through His father, Mirza Abbas, better known as Mirza Buzurg - a nobleman closely associated with the ministerial circles of the Court of Fath-'Ali Shah - to one of the most ancient and renowned families of Mazindaran.
To Him Isaiah, the greatest of the Jewish prophets, had alluded as the "Glory of the Lord," the "Everlasting Father," the "Prince of Peace," the "Wonderful," the "Counsellor," the "Rod come forth out of the stem of Jesse" and the "Branch grown out of His roots," Who "shall be established upon the throne of David," Who "will come with strong hand," Who "shall judge among the nations," Who "shall smite the earth with the rod of His mouth, and with the breath of His lips slay the wicked," and Who "shall assemble the outcasts of Israel, and gather together the dispersed of Judah from the four corners of the earth." Of Him David had sung in his Psalms, acclaiming Him as the "Lord of Hosts" and the "King of Glory." To Him Haggai had referred as the "Desire of all nations," and Zachariah as the "Branch" Who "shall grow up out of His place," and "shall build the Temple of the Lord." Ezekiel had extolled Him as the "Lord" Who "shall be king over all the earth," while to His day Joel and Zephaniah had both referred as the "day of Jehovah," the latter describing it as "a day of wrath, a day of trouble and distress, a day of wasteness and desolation, a day of darkness and gloominess, a day of clouds and thick darkness, a day of the trumpet and alarm against the fenced cities, and against the high towers." His Day Ezekiel and Daniel had, moreover, both acclaimed as the "day of the Lord," and Malachi described as "the great and dreadful day of the Lord" when "the Sun of Righteousness" will "arise, with healing in His wings," whilst Daniel had pronounced His advent as signalizing the end of the "abomination that maketh desolate."
To His Dispensation the sacred books of the followers of Zoroaster had referred as that in which the sun must needs be brought to a standstill for no less than one whole month. To Him Zoroaster must have alluded when, according to tradition, He foretold that a period of three thousand years of conflict and contention must needs precede the advent of the World-Savior Shah-Bahram, Who would triumph over Ahriman and usher in an era of blessedness and peace.
He alone is meant by the prophecy attributed to Gautama Buddha Himself, that "a Buddha named Maitreye, the Buddha of universal fellowship" should, in the fullness of time, arise and reveal "His boundless glory." To Him the Bhagavad-Gita of the Hindus had referred as the "Most Great Spirit," the "Tenth Avatar," the "Immaculate Manifestation of Krishna."
To Him Jesus Christ had referred as the "Prince of this world," as the "Comforter" Who will "reprove the world of sin, and of righteousness, and of judgment," as the "Spirit of Truth" Who "will guide you into all truth," Who "shall not speak of Himself, but whatsoever He shall hear, that shall He speak," as the "Lord of the Vineyard," and as the "Son of Man" Who "shall come in the glory of His Father" "in the clouds of heaven with power and great glory," with "all the holy angels" about Him, and "all nations" gathered before His throne. To Him the Author of the Apocalypse had alluded as the "Glory of God," as "Alpha and Omega," "the Beginning and the End," "the First and the Last." Identifying His Revelation with the "third woe," he, moreover, had extolled His Law as "a new heaven and a new earth," as the "Tabernacle of God," as the "Holy City," as the "New Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband." To His Day Jesus Christ Himself had referred as "the regeneration when the Son of Man shall sit in the throne of His glory." To the hour of His advent St. Paul had alluded as the hour of the "last trump," the "trump of God," whilst St. Peter had spoken of it as the "Day of God, wherein the heavens being on fire shall be dissolved, and the elements shall melt with fervent heat." His Day he, furthermore, had described as "the times of refreshing," "the times of restitution of all things, which God hath spoken by the mouth of all His holy Prophets since the world began."
To Him Muhammad, the Apostle of God, had alluded in His Book as the "Great Announcement," and declared His Day to be the Day whereon "God" will "come down" "overshadowed with clouds," the Day whereon "thy Lord shall come and the angels rank on rank," and "The Spirit shall arise and the angels shall be ranged in order." His advent He, in that Book, in a surih said to have been termed by Him "the heart of the Qur'an," had foreshadowed as that of the "third" Messenger, sent down to "strengthen" the two who preceded Him. To His Day He, in the pages of that same Book, had paid a glowing tribute, glorifying it as the "Great Day," the "Last Day," the "Day of God," the "Day of Judgment," the "Day of Reckoning," the "Day of Mutual Deceit," the "Day of Severing," the "Day of Sighing," the "Day of Meeting," the Day "when the Decree shall be accomplished," the Day whereon the second "Trumpet blast" will be sounded, the "Day when mankind shall stand before the Lord of the world," and "all shall come to Him in humble guise," the Day when "thou shalt see the mountains, which thou thinkest so firm, pass away with the passing of a cloud," the Day "wherein account shall be taken," "the approaching Day, when men's hearts shall rise up, choking them, into their throats," the Day when "all that are in the heavens and all that are on the earth shall be terror-stricken, save him whom God pleaseth to deliver," the Day whereon "every suckling woman shall forsake her sucking babe, and every woman that hath a burden in her womb shall cast her burden," the Day "when the earth shall shine with the light of her Lord, and the Book shall be set, and the Prophets shall be brought up, and the witnesses; and judgment shall be given between them with equity; and none shall be wronged...
To attempt an exhaustive survey of the prophetic references to Baha'u'llah's Revelation would indeed be an impossible task. To this the pen of Baha'u'llah Himself bears witness: "All the Divine Books and Scriptures have predicted and announced unto men the advent of the Most Great Revelation. None can adequately recount the verses recorded in the Books of former ages which forecast this supreme Bounty, this most mighty Bestowal."
In conclusion of this theme, I feel, it should be stated that the Revelation identified with Baha'u'llah abrogates unconditionally all the Dispensations gone before it, upholds uncompromisingly the eternal verities they enshrine, recognizes firmly and absolutely the Divine origin of their Authors, preserves inviolate the sanctity of their authentic Scriptures, disclaims any intention of lowering the status of their Founders or of abating the spiritual ideals they inculcate, clarifies and correlates their functions, reaffirms their common, their unchangeable and fundamental purpose, reconciles their seemingly divergent claims and doctrines, readily and gratefully recognizes their respective contributions to the gradual unfoldment of one Divine Revelation, unhesitatingly acknowledges itself to be but one link in the chain of continually progressive Revelations, supplements their teachings with such laws and ordinances as conform to the imperative needs, and are dictated by the growing receptivity, of a fast evolving and constantly changing society, and proclaims its readiness and ability to fuse and incorporate the contending sects and factions into which they have fallen into a universal Fellowship, functioning within the framework, and in accordance with the precepts, of a divinely conceived, a world-unifying, a world-redeeming Order.
Shoghi Effendi: God Passes By, pages 93-100