What is the meaning for "Vicarius Filii Dei"?

The Latin phrase "Vicarius Filii Dei" means "Vicar of the Son of God." This phrase is in the Donation of Constantine, in which it is used as a title of St. Peter. Some people have claimed that it is still used as a title for the Pope, but the RCC vigorously denies this.

Interest in the phrase stems from the observation that if the roman numeral values of the letters are summed, the total is 666, as below:

V - 5
i - 1
c - 100
a
r
i - 1
u - 5 (in Latin, v's and u's were the same letter)
s
F
i - 1
l - 50
i - 1
i - 1
D - 500
e
i - 1

5+1+100+1+5+1+50+1+1+500+1 = 666.

It is claimed that "Vicarius Filii Dei" is written on the Papal Tiara, but there are in fact multiple Papal Tiaras, only one of which has any writing on it: "Christi Vicario in Terra Regum". No evidence has been produced to support the contention that "Vicarius Filii Dei" is used as a title of the Pope and historians and academics view the story as an urban legend.

The name Vicarius Filii Dei is not an official title of the Pope and never has been. The pope has dozens of titles, but not this one. The closest one to this is Vicarius Christi. The reason the title Vicarius Filii Dei was invented was because Protestants wanted to use a deceitful way to make the pope look bad because if you add up the Roman letters, you get the number 666. But this number can be attained from many people's names, and is completely meaningless. It is even more meaningless given the fact that it is invented. An example of a name which can be converted into 666 is that of "Ellen Gould White", founder of the Seventh Day Adventists. No one accepts this theory either.

Just a correction on some of the user comments. The correlation of Vicarius Filii Dei with 666 was made long before Ellen White or the Seventh-day Adventist Church. The first person I know of to make this connection was Andreas Helwig in 1612 in his book The Roman Antichrist.

Ellen White never applied 666 in this way in any of her writings. This can be verified at: http://www.whiteestate.org/ where there is a searchable database of her writings.

it is the name written or inscribe on the pope's mitre. by counting the letters thats is written on it, according to what the bible says thats how you came about with the number 666. 666 in not the mark of the beast! people say it is, but ut's not. to make it clea for you the mark of the beast is the NATIONAL SUNDAY LAW. you can read revelation 13&14 for more details, thats if you understand prophecy.