God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets,
Hath in these last days spoken unto us IN ->(ἐν) his Son, whom he hath appointed heir of all things, through whom also he made the worlds;
Who being the brightness of his glory, and the express image of his person, and upholding all things by the word of his power, when he had by himself purged our sins, sat down on the right hand of the Majesty on high;
"IN" and as confirmed in John 14:10, God (Yahweh) in the Temple (Jesus).
ONLY spoken in Jesus in these Last days, after his Baptism (pretty much).
"Express image" as when he spoke he expressed out the word.
You could say, If you have seen, heard me, you have seen, heard the Father.
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I'll explain what is meant by Hebrew 1:1-2 to you
The same God who spoke of old through the prophets reserved a more noble means of communication for humanity in the setting up of the new covenant, seeing that he did so "in his Son."
In Old Testament times God spoke to people through Israelite prophets, but now he speaks more directly, for he speaks through his Son. In addition, his revelation is much clearer, for Jesus Christ is the exact expression of the divine nature. All things were created by him, are controlled by him, and one day will return to him as his rightful possession
The old system was communicated through many persons, the new through the Son alone; and a proper understanding of that epic truth will dispel forever any notion that there could be any prophet, leader, or any other type of seer in the Christian dispensation, with a valid message from God. For God to communicate to mankind through any such persons would be a reversion to the old system and why any new prophets like in Islam or any other is out of the question and to why its called the Last days, no more revelations of God.
"IN" and as confirmed in John 14:10, God (Yahweh) in the Temple (Jesus).
The above “IN “got nothing to do with John 14:10 and God (Yahweh) in the Temple (Jesus). see above
"Express image" as when he spoke, he expressed out the word.
Christ is more then just what he spoke, eg, Paul says 1 Cor 15:16 For if the dead are not raised, neither has Christ been raised, 17 and if Christ has not been raised, your faith is vain; you are still in your sins. 18 Then those who have fallen asleep in Christ have perished. So here we see, all that Christ did especially his death and resurrection expressed the image of who He is, exact expression of the divine nature , the “Word” becoming flesh in order of showing us who the Father is / Father is like.
