Jesus made it clear that nobody had ever seen God- "No man hath seen God at any time; the only begotten Son, which is in the bosom of the Father, he hath declared him" (John 1:18)
Even Moses never saw him- "When my glory passes by, I will put you in a cleft in the rock and cover you with my hand until I have passed by. Then I will remove my hand and you will see my back; but my face must not be seen.” (Exodus 33:21-23)
He never actually appeared to Moses at the burning bush, his voice simply came out of it..:)
Yes Jesus does make it very clear in John 6:46, exactly what He means
"Not that anyone has seen the Father, except He who is from God; He has seen the Father"
The same is in John 1:18, in the Original reading
"No one has ever seen God. The unique God, who is close to the Father's side, has revealed Him"
It is clear here, that the first use of "God" is the Father, as the verse explains
In Exodus chapter 33, we read, “and Yahweh said to Moses...You cannot see My face; for no man shall see Me, and live” (verses 17, 20). Yet, in verse 11 it says, “So
Yahweh spoke to Moses Face to face, as a man speaks to his friend”. “pānîm ’el-pānîm”, can also mean, “Person to person”. It is clear that Yahweh here is Speaking directly to Moses, as do friends with each other. The detailed description shows that it is not a dream or vision. In verse 9 we read, “the pillar of cloud descended and stood
at the door of the tabernacle”, and 10, “All the people saw the pillar of cloud standing
at the tabernacle door, and all the people rose and worshipped, each man
in his tent door”. Yahweh was in this Pillar of cloud, Whom Moses saw. In Deuteronomy 34:10, we read, “No prophet has arisen again in Israel like Moses, whom
Yahweh knew Face to face (pānîm ’el-pānîm)”. It is clear from Exodus 33, that there are TWO Persons Who are Yahweh. The One Who meets Moses “Face to face”, as do humans when they meet each other; and the Other, Who says that no one can ever see His Face and live! The One is Jesus Christ, and the Other, The Father. There is no other explanation for this passage.
In Genesis 32, we read, “Jacob was left alone, and a Man wrestled with him until daybreak” (verse 24). This “Man” Who Jacob wrestled with, was actually “physically” with him. In verse 30, Jacob says, “Jacob then named the place Peniel, For I have seen
God Face to face (’ĕlōhîm pānîm ’el-pānîm), he said, and I have been delivered”. Jacob is clear that the “Man”, Whom he wrestled with, is none other than Almighty God.
In Numbers 14:14, “They will tell it to the inhabitants of this land. They have heard that You, Lord, are among these people, how
You, Yahweh, are seen Face to face (‘ayin bə‘ayin,
Eye to eye), how Your cloud stands over them, and how You go before them in a pillar of cloud by day and in a pillar of fire by night”
Deuteronomy 5:4, “Yahweh spoke to you
Face to face (pānîm ’el-pānîm) from the fire on the mountain”
All these Encounters are without doubt, directly with Almighty God Himself. Who is Yahweh. As this cannot be the Father, it can only be the pre-Incarnational Appearances of the Lord Jesus Christ, known as Theophanies, or Christophanies.
No doubt that it is God the Father (YHWH) Who cannot be seen; but God the Son, also YHWH, was seen FACE TO FACE.
