Read Genesis 18 closely. Count the number of persons called God.
Three men approach Abraham. Abraham goes with the three me. God says he must go down to Sodom. The men leave, yet Abraham is still there with God. Abraham is negotiating with God on how many righteous men he would save Sodom for. Then God goes on his way.
Chapter 19, we see two angels in Sodom, everyone knows what happens. But in verse 24 it said God rained fire and sulphur from God out of heaven.. what? Interesting language use here.
But If you keep digging, you’ll keep seeing reference to the Angel of the Lord being called God.
Judges 6, the Angel of the Lord appears before Gideon. Gideon feeds him and then the Angel of the Lord disappears. Gideon becomes terrified when he realizes who the Angel of the Lord is.
22 Then Gideon perceived that it was the angel of the Lord, and Gideon said, “Help me, Lord God! For I have seen the angel of the Lord face to face.”23 But the Lord said to him, “Peace be to you; do not fear; you shall not die.”
Why would Gideon become terrified of dying seeing just an angel? People died seeing God face to face.
Turn to Judges 13. The Angel of the Lord comes to Manoah’s wife. Manoah’s wife leads Manoah to this man. Manoah offers the man, who is the Angel of the Lord, food.
15 Manoah said to the angel of the Lord, “Allow us to detain you and prepare a kid for you.”
Eventually Manoah sees this man ascend to heaven in a flame, and Manoah becomes terrified when he realizes who this man is.
Then Manoah realized that it was the angel of the Lord. 22 And Manoah said to his wife, “We shall surely die, for we have seen God.”
Manoah realizes this man, the Angel of the Lord is God. He is terrified of dying because he has seen God.
But pay attention to verse 8 and 9
8 Then Manoah entreated the Lord and said, “O my Lord, I pray, let the man of God whom you sent come to us again and teach us what we are to do concerning the boy who will be born.” 9 God listened to Manoah, and the angel of God came again to the woman as she sat in the field, but her husband Manoah was not with her.
Manoah prayed to God that this man.. whom Manoah later realized is God, would appear. And God sends this man to Manoah.
Do the math. How many persons are God here?
Exodus 3, who is in the burning bush? Verse 2 says the Angel of the Lord. When Moses turns aside, God calls out to Abraham from the burning bush.
In Judaism there was the thought of two powers in heaven. Yahweh and the Angel of Yahweh. Both God. It later became a heresy in 2nd century Rabbinic Judaism because early Christians were pointing to the Angel of the Lord as being an early Christophany.
The early Jewish followers of Christ saw no issue with worshipping Jesus because it was part of Judaism that there were two Yahwehs. Yahweh and the Angel of Yahweh, both called God, yet they only worshipped one God.
The examples I provided of this are far from being all the times in the Old Testament this happens.
https://bibleproject.com/articles/who-is-the-angel-of-the-lord/