Well, he did per Hebrews 1. It's just that disctinction is not always made. It's the same with claiming Jesus is descended from David. That's only true if you recognoze the stepfather Joseph. If this is not true, how do you explain the verses of 'today' you become my son in Hebrews 1?
The Abingdon Bible Commentary of 1929 (compiled by some 66 professors of biblical exegesis, biblical languages, theology, Christian doctrine and church history etc.) has the following to say with reference to the words “express image” (KJV) “The word translated ‘very image’ means, literally, the stamp cut by a die, and so the impress made upon a seal; thus the phrase signifies that the essence of the divine nature was stamped on the Person of Christ. He was the ‘impress of God‘s essence.”(Professor H. T Andrews, D.D., The Abingdon Bible Commentary, 1929) So what does it mean to say that Christ is the “express image” (exact impress) of God’s person? In this Scripture (Hebrews 1:3), the Greek word translated “person” is hupostasis.
It is a compound of two other Greek words. These words are hupo meaning literally under (Matthew 5:15, Luke 13:34, Acts 2:5 and Romans 16:20 etc.) and histemi meaning to be stood, stand, standing, set or be established (see Matthew 2:9, 6:5, 18:16, Mark 9:36, John 1:26, and Acts 24:21). We can see therefore that hupostasis means the foundation or under-girding (sub-structure or substance) of cause of being, or, to put it another way, the essential structure of what makes something what it is. Christ therefore is the “express image” (stamp/impress) of the substance/foundation/under-girding of God. In other words, what God is so is the Son. In this respect they are one and the same. One though, the Son, is the image. Paul noticeably avoided using words that could make it appear he was saying it was only in outward appearance that Christ was the “express image” of God’s person. One such word is prosopon, meaning the countenance or appearance (i.e. that which is visibly seen, the visage). We can see therefore that the word hupostasis does not refer to exterior appearance. This can be seen even more clearly when we see how the same author uses this word in Hebrews 3:14 “For we are made partakers of Christ, if we hold the beginning of our confidence [hupostasis] stedfast unto the end” Hebrews 3:14 This “confidence” is the substance of our hope (it is that of which our hope is made, the foundation or under-girding). As Paul explains as he uses this Greek word for the third time in this epistle “Now faith is the substance [hupostasis] of things hoped for, the evidence of things not seen.” Hebrews 11:1 The substance/confidence (hupostasis) is the ‘stuff’ of which our hopes are made. It is our faith, the foundation or under-girding of our hopes. Take note of how William Tyndale translated Hebrews 1:3. His was a 16th century translation into English “Which sonne beynge the brightnes of his glory and very ymage of his substance bearinge vp all thinges with the worde of his power hath in his awne person pourged oure synnes and is sitten on the right honde of the maiestie an hye” Hebrews 1:3 Tyndale’s translation 1525 Tyndale’s translation says that the Son is the “very ymage” of God’s “substance”. This is in contrast to the formulators of the KJV who translated hupostasis as “person”. The earlier translation is much clearer to us today than the KJV. It shows exactly what Paul meant by his use of hupostasis. It is referring to God’s very (inner) being (
what God is). It is that which makes God God. It is His substructure. Unfortunately today, when we say person, we simply think of this as the entirety of a human being when in fact it can mean the actual self or personality (inner nature/being) of a human being.