This is an accusation made by the Seventh Day Adventists against the Catholic Church.
Seventh Day Adventists are making an accusation against the Catholic Church. They are saying that, "The Pope is the Antichrist" with this as evidence: VICARIUS FILII DEI (Vicar of the Son of God) which sums up to 666. They often use Revelation 13:16-18 as an attack to the Catholic Church:
Revelation 13:16-18, "And he caused all, both small and great, rich and poor, free and bond to receive a mark on their right hand and on their foreheads containing the mark of the beast or the number bearing his name. Here is wisdom:
 Let him who is intelligent calculate the number of the beast for it is a man's number, his number is 666"
Note: The VICARIUS FILII DEI, was it seen on the Pope's tiara? The SDAs are very clever to exchange "CHRISTI" in VICARIUS CHRISTI (Vicar of Christ) to FILII DEI since Christi is Filii Dei. What these SDAs do not know is there are official titles of the Pope which didn't sum up to 666. Here are those:
1. Vicar of Christ
2. Bishop of Rome
3. Supreme Pontiff (Bridge-Builder)
4. Successor of Peter
5.Patriarch of the West
6. The Primate of Italy
7. Sovereign of the Vatican State
Where is the "VICARIUS FILII DEI" there in the official, not distorted titles of the Pope? Here's more, they are saying that the Roman Catholic Church is the Whore of Babylon. They use Revelation 17:18 to prove that.
Revelation 17:18, "The woman which you saw is 
the great city ruling upon the kings of the earth"
They conclude that the Roman Church is that Whore because it sits upon seven hills. The question, was Vatican Hill on where the Roman Church was built one of the seven hills of Rome? Here's the list of Rome's seven hills:
| Aventinus (Aventine)
Caelius (Caelian)
Capitolium (Capitoline)
Esquiliae (Esquiline)
Palatium (Palatine)
Quirinalis (Quirinal)
Viminalis (Viminal)
 | 
 | 
 | 
 | 
Source: http://www.musesrealm.net/rome/sevenhills.html
Where is the Vatican Hill there? And Revelation 17 aims to attack the pagan Roman emperors like Nero, Domitian, Trajan, Diocletian and so on. It was not aimed to attack the Roman Christians, in fact, Paul wrote his letter to the Roman Christians:
Romans 1:7-8, "And so I write to you in Rome, whom God has called to be His people. May God our Father and the Lord Jesus Christ give you grace and peace. 
First of all, I want to thank God through Jesus Christ for you since the whole world is hearing about your faith"
See? The whole world is hearing about the faith of the Roman Christians, that is us, not the Seventh Day Adventists whose sect had been invented just recently. In fact, if we are going to examine Ellen White's name, it would sum up to 666:
E-0
L-50
L-50
E-0
N-0
G-0
O-0
U-5
L-50
D-500
W-10
H-0
I-1
T-0
E-O
-------------------
= 666
See? Revelation 13:18 suits EGW more than the Papacy. This is also adapted by the Iglesia ni Cristo (of Manalo) and Eli Soriano's Members of the Church of God International (or commonly known as Ang Dating Daan or The Old Path). But this has been off base already by Catholic apologists.
Here are some of EGW's failed prophecies:
JERUSALEM'S FUTURE
An 
interesting prophecy of Mrs. White's was that "Old Jerusalem never would
 be built up". In Early Writings p 75, she said, "Then I was pointed to 
some who are in the great error of believing that it is their duty to go
 to Old Jerusalem, and think they have a work to do there before the 
Lord comes .... I saw that Satan had greatly deceived some in this 
thing, .... I ALSO SAW THAT OLD JERUSALEM NEVER WOULD BE BUILT UP; and 
that Satan was doing his utmost to lead the minds of the children of the
 Lord into these things now, in the gathering time" (emphasis added).
This prophecy did not come true. Since the nation of Israel's rebirth in 1948, "old Jerusalem" has been greatly built up.
MRS. WHITE ALIVE WHEN JESUS RETURNS
Mrs. White predicted that she would be among "the living saints" when Jesus returned.
"Soon 
our eyes were drawn to the east, for a small black cloud had appeared, 
about half as large as a man's hand, which we all knew was the sign of 
Son of man.... Then there was a mighty earthquake. The graves opened, 
and the dead came up clothed with immortality. The 144,000 shouted, 
"Alleluia!" as they recognized their friends who had been torn from them
 by death, and in the same moment WE WERE CHANGED AND CAUGHT UP TOGETHER
 WITH THEM to meet the Lord in the air". Early Writings, pp 15-16 
(emphasis added).
ENGLAND WILL ATTACK THE UNITED STATES
In 1862 
she predicted that "when England does declare war [against the North, 
during the civil war]. all nations will have an interest of their own to
 serve, and there will be general war, general confusion." The result 
will be that "this nation [the United States] will...be humbled into the
 dust". Testimonies for the Church, vol. 1, p. 259.
American
 history clearly shows that England did not "declare war" against the 
United States during the Civil War, and the United States was not 
"humbled into the dust". 
THE CIVIL WAR IS A SIGN THAT JESUS IS ABOUT TO RETURN
"I saw 
greater distress in the land than we have yet witnessed. I heard groans 
and cries of distress, and saw large companies in active battle. I heard
 the booming of the cannon, the clash of arms, the hand-to-hand fight, 
and the groans and prayers of the dying....God's people must take 
warning and discern the signs of the times. The signs of Christ's coming
 are too plain to be doubted, and in view of these things everyone who 
professes the truth should be a living preacher....All heaven is astir. 
THE SCENES OF EARTH'S HISTORY ARE FAST CLOSING. We are amid the perils 
of the last days". Testimonies for the Church, vol. 1, p. 260 (emphasis 
added)
IN THE 1850'S MRS. WHITE SAID JESUS WAS TO RETURN "IN A FEW MONTHS"
"Some 
are looking too far off for the coming of the Lord. Time has continued a
 few years longer than they expected; therefore they think it may 
continue a few years more, and in this way their minds are being led 
from present truth, out after the world.... I saw that the time for 
Jesus to be in the most holy place was nearly finished and that TIME CAN
 LAST BUT A VERY LITTLE LONGER". Early Writings, p. 58 (emphasis 
added)."
In a 
view given June 27, 1850, my accompanying angel said, "TIME IS ALMOST 
FINISHED....Said the angel, "Get ready, get ready, get ready...." I saw 
that there was a great work to do for them and but LITTLE TIME in which 
to do it....Then I saw that THE SEVEN LAST PLAGUES WERE SOON TO BE 
POURED OUT upon those who have no shelter...."
Early Writings, p 64 (emphasis added).
Mrs. 
White continues to relate her vision and makes a startling prediction 
that only a few months are left before the Lord will return. "But NOW 
TIME IS ALMOST FINISHED and what we have been years learning, they will 
have to learn in a FEW MONTHS. They will also have much to unlearn and 
much to learn again." Early Writings, p 67 (emphasis added). 
ADVENTISTS LIVING IN 1856 WILL BE ALIVE TO SEE JESUS RETURN
Over 135
 years ago, Mrs. White made another fascinating prophecy during a 
meeting in Battle Creek, Michigan in May of 1856. She declared that some
 of those who were at the meeting would die, and become "food for 
worms," and that some of them would live on and become "subjects of the 
seven last plagues," while still others would "remain upon the earth to 
be translated at the coming of Jesus". Testimonies for the Church, vol. 
1, pp. 131-132.
CHRIST WOULD RETURN BEFORE SLAVERY WAS ABOLISHED
"I saw 
the pious slave rise in triumph and victory and shake off the chains 
that bound him, while his wicked master was in confusion and knew not 
what to do; for the wicked could not understand the words of the voice 
of God. Soon appeared the great white cloud ....On it sat the Son of 
man." Early Writings, pp 35
"I saw 
that the slave master will have to answer for the soul of his slave whom
 he has kept in ignorance; and the sins of the slave will be visited on 
the master. God cannot take to heaven the slave who has been kept in 
ignorance and degradation, knowing nothing of God and the Bible, fearing
 nothing but his master's lash, and holding a lower position than the 
brutes. But he does the best thing for him that a compassionate God can 
do. He permits him to be as if he had not been, while the master must 
endure the seven last plagues and then come up in the second 
resurrection and suffer the second, most awful death. Then the justice 
of God will be satisfied."
Early Writings, pp 276
Slavery was not abolished for another 6 years after these statements, and the Lord hadn't yet returned. 
MRS. WHITE SAW ENOCH ON JUPITER OR SATURN
The Lord
 has given me a view of other worlds. Wings were given me, and an angel 
attended me from the city to a place that was bright and glorious. THE 
GRASS OF THE PLACE WAS LIVING GREEN, AND THE BIRDS THERE WARBLED A SWEET
 SONG. THE INHABITANTS OF THE PLACE WERE OF ALL SIZES; THEY WERE NOBLE, 
MAJESTIC, AND LOVELY....I asked on of them why they were so much more 
lovely than those on earth....Then I WAS TAKEN TO A WORLD WHICH HAD 
SEVEN MOONS. There I saw good old Enoch, who had been translated". Early
 Writings, pp. 39-40 (emphasis added)
Ellen's 
husband, James White verified her vision. He wrote, "At our conference 
in Topsham, Maine, last Nov., Ellen has a vision of the handy works of 
God. SHE WAS GUIDED TO THE PLANETS JUPITER, SATURN, AND I THINK ONE MORE. After
 she came out of vision, she could give a clear description of their 
Moons, etc... It is well known that she knew nothing of astronomy, and 
could not answer one question in relation to the planets, before she had
 this vision." A Word to the "Little Flock", p. 22 (emphasis added).
Excellent satellite pictures of Jupiter and Saturn have not revealed any life forms. 
MRS. WHITE SAID THAT WE HAVE ANIMAL ORGANS IN OUR BRAINS AND THE WEARING OF WIGS WOULD CAUSE INSANITY
Mrs. White said:
"Fashion
 loads the heads of women with artificial braids and pads, which do not 
add to their beauty, but give an unnatural shape to the head. The hair 
is strained and forced into unnatural positions, and it is not possible 
for the heads of these fashionable ladies to be comfortable. The 
artificial hair and pads covering the base of the brain, heat and excite
 the spinal nerves centering in the brain. The head should ever be kept 
cool. The heat caused by these artificials induces the blood to the 
brain. The action of the blood upon the lower or animal organs of the 
brain, causes unnatural activity, tends to recklessness in morals, and 
the mind and heart is in danger of being corrupted. As the animal organs
 are excited and strengthened, the moral are enfeebled. The moral and 
intellectual powers of the mind become servants to the animal. In 
consequence of the brain being congested its nerves lose their healthy 
action, and take on morbid conditions, making it almost impossible to 
arouse the moral sensibilities. Such lose their power to discern sacred 
things. The unnatural heat caused by these artificial deformities about 
the head, induces the blood to the brain, producing congestion, and 
causing the natural hair to fall off, producing baldness. Thus the 
natural is sacrificed to the artificial."Many have lost their reason, 
and become hopelessly insane, by following this deforming fashion. Yet 
the slaves to fashion will continue to thus dress their heads, and 
suffer horrible disease and premature death, rather than be out of 
fashion."
- The Health Reformer, October 1, 1871
- Second Advent Review and Sabbath Herald, October 17, 1871
A SCRIPTURAL WARNING!!!
"But
 the prophet, which shall presume to speak a word in my name, which I 
have not commanded him to speak, or that shall speak in the name of 
other gods, even that prophet shall die. And if thou say in thine heart,
 How shall we know the word which the LORD hath not spoken? WHEN A 
PROPHET SPEAKETH IN THE NAME OF THE LORD, IF THE THING FOLLOW NOT, NOR 
COME TO PASS, THAT IS THE THING WHICH THE LORD HATH NOT SPOKEN, but the 
prophet hath spoken it presumptuously: thou shalt not be afraid of him."
 Deuteronomy 18:20-22 (emphasis added) 
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