The Son is the image of the invisible God, the firstborn over all creation.
For by him [The First Born Son] all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things have been created by him and for him.
He is before all things, and in him all things hold together.
He [Jesus] was in the world, and the world was made by Him [Jesus], and the world did not know Him.
Long ago, at many times and in many ways, God spoke to our fathers by the prophets, 2 but in these last days he has spoken to us by his Son, whom he appointed the heir of all things, through whom also he created the world. 3 He [Jesus] is the radiance of the glory of God and the exact imprint of his nature, and he upholds the universe by the word of his [Jesus'] power. After making purification for sins, he sat down at the right hand of the Majesty on high,
In the beginning was the Word, and the Word was with God, and the Word [Jesus] was God.
By means of the First Born Son [The Word], God created the Heavens and the Earth.
And they heard the Voice [The Word/The First Born Son] of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God [The Word/The First Born Son] among the trees of the garden.
And the LORD God [The Word/The First Born Son] called unto Adam, and said unto him, Where are you?
The FIRST time in history that the Father speaks in His Own Voice, rather than using the mediator of The Word/His First Born Son, is in Mark 1:11 and Matthew 3:17:
And a voice came from heaven, “You are my beloved Son; with you I am well pleased.”
How to find The Father in the Hebrew Bible/Old Testament:
In King James, New American Standard, International Standard Version, and English Standard Version = Lord GOD
How to find the First Born Son/The Word in the Hebrew Bible/Old Testament = LORD God
If you would like to see The Word and The Father in their Old Testament roles-- the Father speaking through The Word/LORD God, the following is a good clear example:
Again the Word of the LORD [THE FIRSTBORN SON] came to me: 2“Son of man, make known to Jerusalem her abominations, 3and say, Thus says the Lord GOD [The Father] to Jerusalem....