Authenticity

In the arts, history, archaeology, the study of antiques, and similar fields involving unique or scarce artifacts from the past, and, with regard to documents in law, authenticity (Greek: ἀρχηγός from 'archēgos'='author').

1.  the chief leader, prince
    - of Christ
2. one that takes the lead in any thing and thus affords an example, a predecessor in a matter, pioneer
3. the author

Strong's Number: 747 Greek: archegos
Author: translated "Prince" in Act 3:15 (marg., "Author") and Acts 5:31, but "Author" in Hebrews 2:10, RV, "Captain," RV marg., and AV, and "Author" in Hebrews 12:2, primarily signifies "one who takes a lead in, or provides the first occasion of,anything." In the Septuagint it is used of the chief of a tribe or family, Numbers 13:2 (RV, prince); of the "heads" of the children of Israel, Numbers 13:3; a captain of the whole people, Numbers 14:4; in Micah 1:13, of Lachish as the leader of the sin of the daughter of Sion: there, as in Hebrews 2:10, the word suggest a combination of the meaning of leader with that of the source from whence a thing proceeds. That Christ is the Prince of life signifies, as Chrysostom says, that "the life He had was not from another; the Prince or Author of life must be He who has life from Himself." But the word does not necessarily combine the idea of the source or originating cause with that of leader. In Hebrews 12:2 where Christ is called the "Author and Perfecter of faith," He is represented as the one who takes precedence in faith and is thus the perfect Exemplar of it. The pronoun "our" does not correspond to anything in the original, and may well be omitted. Christ in the days of His flesh trod never deviating the path of faith, and as the Perfecter has brought it to a perfect end in His own person. Thus He is the leader of all others who tread that path.

In Acts 28:16 some mss. have the word stratopedarches (lit., "camp-commander"), which some take to denote a praetorian prefect, or commander of the praetorian cohorts, the Emperor's bodyguard, "the captain of the praetorian guard." There were two praetorian prefects, to whose custody prisoners sent bound to the Emperor were consigned. But the word probably means the commander of a detached corps connected with the commissariat and the general custody of prisoners.

Prince:
primarily an adjective signifying "originating, beginning," is used as a noun, denoting "a founder, author, prince or leader," Acts 3:15, "Prince" (marg., "Author"); Acts 5:31

As Christians

In one sense, the idea of being authentic really has a lot to do with the ways that we, as Christians, know we ought to act, and ways in which we would want others to perceive us, and ways that people talk about us with others.
For example, here are two possible ways someone might be referred to:

1. "Oh, that Bob, he's such a liar."
2. "Oh, that Bob, you can trust him."

If there is really no good reason to suggest, or even suspect, that Bob might be a liar, it's not very likely that anyone would say that Bob is a such a liar. On the other hand, if someone is commonly referred to as a liar there is a good chance they probably are one.

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