You asked: Why is The Urantia Book called the Fifth Epochal Revelation?

There have been many events of religious revelation but only five of epochal significance. These were as follows:

1. The Dalamatian teachings. The true concept of the First Source and Center was first promulgated on Urantia by the one hundred corporeal members of Prince Caligastia’s staff. This expanding revelation of Deity went on for more than three hundred thousand years until it was suddenly terminated by the planetary secession and the disruption of the teaching regime. Except for the work of Van, the influence of the Dalamatian revelation was practically lost to the whole world. Even the Nodites had forgotten this truth by the time of Adam’s arrival. Of all who received the teachings of the one hundred, the red men held them longest, but the idea of the Great Spirit was but a hazy concept in Amerindian religion when contact with Christianity greatly clarified and strengthened it.
2. The Edenic teachings. Adam and Eve again portrayed the concept of the Father of all to the evolutionary peoples. The disruption of the first Eden halted the course of the Adamic revelation before it had ever fully started. But the aborted teachings of Adam were carried on by the Sethite priests, and some of these truths have never been entirely lost to the world. The entire trend of Levantine religious evolution was modified by the teachings of the Sethites. But by 2500 B.C. mankind had largely lost sight of the revelation sponsored in the days of Eden.
3. Melchizedek of Salem. This emergency Son of Nebadon inaugurated the third revelation of truth on Urantia. The cardinal precepts of his teachings were trust and faith. He taught trust in the omnipotent beneficence of God and proclaimed that faith was the act by which men earned God’s favor. His teachings gradually commingled with the beliefs and practices of various evolutionary religions and finally developed into those theologic systems present on Urantia at the opening of the first millennium after Christ.
4. Jesus of Nazareth. Christ Michael presented for the fourth time to Urantia the concept of God as the Universal Father, and this teaching has generally persisted ever since. The essence of his teaching was love and service, the loving worship which a creature son voluntarily gives in recognition of, and response to, the loving ministry of God his Father; the freewill service which such creature sons bestow upon their brethren in the joyous realization that in this service they are likewise serving God the Father.
5. The Urantia Papers. The papers, of which this is one, constitute the most recent presentation of truth to the mortals of Urantia. These papers differ from all previous revelations, for they are not the work of a single universe personality but a composite presentation by many beings. But no revelation short of the attainment of the Universal Father can ever be complete. All other celestial ministrations are no more than partial, transient, and practically adapted to local conditions in time and space. While such admissions as this may possibly detract from the immediate force and authority of all revelations, the time has arrived on Urantia when it is advisable to make such frank statements, even at the risk of weakening the future influence and authority of this, the most recent of the revelations of truth to the mortal races of Urantia. ~ The Urantia Book, 92:4.4

Click to read about The gift of revelation

What is Epochal Revelation?

Epochal revelation is a concept that is unique to The Urantia Book; this concept is quite useful in understanding the history of our earth (Urantia) and is vital to carrying an individual past the purely evolutionary religious experience to the revelatory experience of what Jesus called “true religion.”

Epochal revelation is always concerned with the advancement of religion, and new knowledge about God.

The evolutionary picture of human existence begins and ends with religion, albeit very different qualities of religion, one evolutional and biological, the other revelational and periodical. ~ The Urantia Book, 5:5.5

Only two influences can modify and uplift the dogmas of natural religion: the pressure of the slowly advancing mores and the periodic illumination of epochal revelation. ~ The Urantia Book, 92:3.5

Truth is always a revelation: autorevelation when it emerges as a result of the work of the indwelling Adjuster; epochal revelation when it is presented by the function of some other celestial agency, group, or personality. ~ The Urantia Book, 101:4.3

The Function of Epochal Revelation:

Revelation is a technique whereby ages upon ages of time are saved in the necessary work of sorting and sifting the errors of evolution from the truths of spirit acquirement. ~ The Urantia Book, 101:5.1

It is the mission of revelation to sort and censor the successive religions of evolution.~ The Urantia Book, 92:4.1

Evolutionary Religion vs the Religion of Revelation:

Examples of “evolutionary” religion include virtually all institutionalized religions, such as Christianity (all sects), Catholicism, Judaism, Shinto, Islam, Buddhism, etc.; in short, all religions who have had origin as a result of man’s searching for God over the course of history, and growth throughout the generations of man. Evolutionary religion is usually characterized by dogma, by rules, by priests who intervene between man and God, by caveats and warnings, and largely by an underlying fear of God. One learns that in order to gain salvation, one must obey the rules.

Some relevant Urantia Book quotes:

Evolutionary religion may become ethical, but only revealed religion becomes truly and spiritually moral. The olden concept that God is a Deity dominated by kingly morality was upstepped by Jesus to that affectionately touching level of intimate family morality of the parent-child relationship, than which there is none more tender and beautiful in mortal experience.~ The Urantia Book, 2:6.2

Evolutionary religion creates its gods in the image and likeness of mortal man; revelatory religion seeks to evolve and transform mortal man into the image and likeness of God.~ The Urantia Book, 85:6.3

One Asiatic people taught that “God is a great fear”; that is the outgrowth of purely evolutionary religion. Jesus, the revelation of the highest type of religious living, proclaimed that “God is love.” ~ The Urantia Book,92:1.5

Evolutionary belief in ghosts laid the foundation for a philosophy of revealed religion which will eventually destroy the superstition of its origin. ~ The Urantia Book,92:3.5

Evolutionary religion pictures the circuitous gropings of humanity in quest of truth; revelatory religion is that very truth. ~ The Urantia Book,92:4.3

The characteristic difference between evolved and revealed religion is a new quality of divine wisdom which is added to purely experiential human wisdom. But it is experience in and with the human religions that develops the capacity for subsequent reception of increased bestowals of divine wisdom and cosmic insight. ~ The Urantia Book,100:6.9

Evolutionary religion. The experience of primitive worship, the religion which is a mind derivative.

Revealed religion. The universe attitude which is a spirit derivative; the assurance of, and belief in, the conservation of eternal realities, the survival of personality, and the eventual attainment of the cosmic Deity, whose purpose has made all this possible. It is a part of the plan of the universe that, sooner or later, evolutionary religion is destined to receive the spiritual expansion of revelation. ~ The Urantia Book,101:5.41.

Revealed Religion adds Personal Spiritual Experience to Religion

Evolved religion rests wholly on faith. Revelation has the additional assurance of its expanded presentation of the truths of divinity and reality and the still more valuable testimony of the actual experience which accumulates in consequence of the practical working union of the faith of evolution and the truth of revelation.~ The Urantia Book,101:5.12

Evolutionary religion provides only the assurance of faith and the confirmation of conscience; revelatory religion provides the assurance of faith plus the truth of a living experience in the realities of revelation. ~ The Urantia Book,101:5.13

Click to read more about Religion Expanded by Revelation

Click to read Jesus’ Discourse on True Religion

Epochal Revelation is Ordered and Logical

• Epochal revelation builds upon itself; each revelation advances the ideas of the last revelation
• Adam and Eve could came only as a result of the advances made from the Planetary Prince’s reign.
• On our world, Melchizedek came after Adam and Eve (not a normal progression) because of the default of the Edenic pair, and the ensuing loss of the one-God concept among the races of mankind.
• Melchizedek prepared the way for Jesus, who revealed the one-God concept – again in the form of a human being.
• The Urantia Papers came about 2000 years after Jesus, again revealing the loving Father that Jesus had personified for us; The Urantia Book also contains the complete restatement of the life and teachings of Jesus, filling in the gaps in Scripture, which was the only real earthly record of his amazing life up until then.

As an epochal revelation, The Urantia Book is unique, in that it is in the form of a book. All previous revelations have been in the form of personalities: Caligastia, Adam and Eve, Melchizedek, and Jesus of Nazareth.

Is The Urantia Book God’s Final Revelation To Mankind?

The Urantia Book is intended to inform Urantian civilization for the next millennium. Here’s a clue about that from the pages of The Urantia Book (bolding by ed.):

It is not possible to formulate comprehensive and entirely consistent classifications of the personalities of the grand universe because all of the groups are not revealed. It would require numerous additional papers to cover the further revelation required to systematically classify all groups. Such conceptual expansion would hardly be desirable as it would deprive the thinking mortals of the next thousand years of that stimulus to creative speculation which these partially revealed concepts supply. It is best that man not have an overrevelation; it stifles imagination. ~The Urantia Book, 30:0.2

And this:

The papers, of which this is one, constitute the most recent presentation of truth to the mortals of Urantia. These papers differ from all previous revelations, for they are not the work of a single universe personality but a composite presentation by many beings. But no revelation short of the attainment of the Universal Father can ever be complete. All other celestial ministrations are no more than partial, transient, and practically adapted to local conditions in time and space. While such admissions as this may possibly detract from the immediate force and authority of all revelations, the time has arrived on Urantia when it is advisable to make such frank statements, even at the risk of weakening the future influence and authority of this, the most recent of the revelations of truth to the mortal races of Urantia. ~ The Urantia Book, 92:4.4

And so we have the concept of The Urantia Book now-earth’s fifth epochal revelation of God-and yet the door is left open for speculation and anticipation of yet further epochal revelations to come that will help mankind on Urantia to reach ever greater heights in its certain passage to the ages of Light and Life.

When you look over the revelations of God to this planet – the vast time frames. the drama and excitement, the intensity, the disappointment, the victories and the love – we can only have faith that we are never forgotten and that when we need it most, we all have exactly what we need – as an evolutionary planet of time and space, and as beloved individual children of God. It is up to us to take the gift of revelation, let it pass over us and through us and enrich our world with its truths.