Heb. 1:3 in the KJV says, “He is the brightness of His glory and the express image (charakter) of His Person (hypostasis).”
Hebrews 1:3 proves that Jesus Christ is the brightness of the Father’s glory and the express image of the Father’s Person. The Greek word “charakter” proves that Jesus was reproduced as an imprinted copy of the Father’s Person as a human person. According to Strong's Exhaustive Concordance, the short definition of charaktér: (khar-ak-tare') is an “EXACT REPRODUCTION.” A reproduction is something copied from an original.
Thayer's Greek Lexicon says that “charakter” χαρακτήρ means “the mark (figure or letters) stamped upon that instrument or wrought out on it; hence, universally, ‘a mark or figure burned in (Leviticus 13:28) or stamped on, an impression; the exact expression (the image) of any person or thing, marked likeness, PRECISE REPRODUCTION IN EVERY RESPECT’ (cf. facsimile): From the same as charax; a graver (the tool or the person), i.e. (by implication) engraving (“character”), the figure stamped, i.e. AN EXACT COPY or (figuratively) a representation -- express image.”
Under Hebrews 1:3, the Greek–English Lexicon of the New Testament and Other Early Christian Literature, 3rd edition (BDAG) confirms that the Greek noun “CHARAKTER” used in Hebrews 1:3 proves that the Son is God the Father’s “produced … reproduction, representation” as “a human being as the reproduction of his own identity/reality … Christ is an exact representation of God’s real being Hb 1:3.”
Since Hebrews 1:3 clearly states that the Son is “the brightness of his glory and the express image of his person” referencing the Father’s Person, the Son must be the “human being as the reproduction of his (the Father’s) own identity.”
Professor Barry Smith of Atlantic Baptist University wrote in his exegesis on the Letter To The Hebrews 1:3,
“The Greek word (Charakter) can mean the literal imprint of something, that which corresponds to the die. Relatedly, it can refer to something as THE COPY OF AN ORIGINAL. This is confirmed by an inscription on a statue of Antiochus I of Commagene that reads: ‘exact image of my form’” (charaktêra morphês emês) (Dittenberger, Or. 383, 60).
Here we can see that the Greeks often used the word “charakter” as an “exact image” as a statue of a person’s form. Therefore the Greek word “charakter” used in Hebrews 1:3 proves that Jesus is “the image of the invisible God” (Colossians 1:15) as the exact image of the invisible Father’s Person as a visible human person.
Thayer's Greek Lexicon says that “hypostasis” ὑπόστασις translated as Person in the KJV means:
a. that which has actual existence; a SUBSTANCE, REAL BEING
b. the substantial quality, nature, of any person or thing: τοῦ Θεοῦ (R. V. SUBSTANCE), Hebrews 1:3 (Wis. 16:21; ἴδε ... τίνος ὑποστάσεως ἤ τίνος εἴδους τυγχάνουσιν οὕς ἐρεῖτε καί νομιζετε Θεούς, Epist. ad' Diogn. 2, 1 [ET]; (cf. Suicer, Thesaurus, under the word)).
Jesus Christ is therefore the “express image” or the exact “reproduced copy” of the Father’s substance of Being as a genuine human person through his miraculously virgin conception via the Holy Spirit of the only true God the Father who descended upon the Hebrew virgin (Luke 1:35, Matthew 1:20).
The precise meaning of the Greek words “charakter” and “hypostasis” used in Hebrews 1:3 provides irrefutable evidence to show that the Son of God was made via incarnation through the virgin as the “reproduction” or “imprinted copy” of the Father’s substance of Being as a fully complete human being. Therefore Jesus is “the image of the invisible God” as the image of the invisible Father because he was “reproduced” as a “copy” of the Father’s Being within a bodily form.
In the Exegetical Guide to the Greek New Testament; Colossians and Philemon; Colossians 1:15, p. 39, Dr Harris wrote:
The Son is “… (“the image,” “the visible image [NLT],” “the visible representation” [Cassirer]) although anar. An εἰκὼν is a “likeness” or a “visible expression.” The degree of resemblance between the archetype and the copy must be determined by the word’s context but could range from a partial or superficial resemblance to a complete or essential likeness. Given 1:9 and 2:9, εἰκὼν here signifies that Jesus is an exact, as well as a visible, representation of God… The invisible God, who dwells in unapproachable light (I Tim. 6:16), is visibly expressed in his Son (cf. John 1:18; 12:45; 14:9). (Exegetical Guide to the Greek New Testament; Colossians and Philemon; p. 39)
According to Dr Harris, the Greek text in Colossians 1:15 indicates that Jesus is the “visible image”, the “visible representation,” and the visible “copy” of the invisible God. If words mean anything, a visible “image,” “representation,” or “copy” of the invisible God the Father could not be a timeless image, representation, or copy. Therefore the Son had to have had a beginning via his virgin begetting in order to be the visible image or copy of the invisible Father.
Trinitarians cannot explain how an alleged eternal God the Son Person could have always been eternally reproduced as an imprinted copy of the Father's Substance of Being while always existing without a beginning. Revelation 3:14 proves that Jesus is "the beginning of the creation OF GOD." In what sense was Jesus the beginning OF the creation OF God if he never had a beginning? Hence, the Son of God was first conceived in the mind and plan of God as “the image of the invisible God” the Father and “the firstborn of all creation” (Colossians 1:15) before he was literally born as that image later on in time.
“But when the fullness of the time came, God sent forth His Son, born of a woman, born under the Law …” Galatians 4:4