Could you share where a person was named Peter (Kipa, Petros, Cephas, Tsuwr) prior to that point?
(Having said that, I do realize that God identifies Himself as "Rock" several points in the OT, but the way I read it, the expression is primarily used as an adjective, with the following exceptions:
And even those do not reflect so much a "Proper Name" as a metaphor (imho).
One method of Hermeneutical understanding of Matthew 16:18
is to do a word study of all the scriptures which were then known
as the Holy Word of G-d when Y'shua spoke these words.
This will allow one to understand that all of the Holy Word of G-d
was inspired by YHvH; the whole counsel of G-d.
The only conclusion that one can come to unless you are
predisposed to believe in man's tradition over the Holy Word of G-d
is that Y'shua was speaking of himself as the "Rock "
Genesis 49:24 But his bow remained steady, his strong arms stayed
[Or archers will attack...will shoot...will remain...will stay] supple,
because of the hand of the Mighty One of Jacob,
because of the Shepherd, the Rock of Israel,
Deuteronomy 32:3 I will proclaim the name of the LORD. Oh, praise the greatness of our God!
Deuteronomy 32:4 He is the Rock , his works are perfect, and all his ways are
just. A faithful God who does no wrong, upright and just is he.
Deuteronomy 32:15 ..... He abandoned the God who made him and rejected the Rock his Saviour.
Deuteronomy 32:30 How could one man chase a thousand, or two put ten
thousand to flight, unless their Rock had sold them, unless
the LORD had given them up?
Deuteronomy 32:31 For their rock is not like our Rock , as even our enemies concede
Deuteronomy 32:32 Their vine comes from the vine of Sodom and from the fields of Gomorrah.
Their grapes are filled with poison, and their clusters with bitterness.
1 Samuel 2:2 "There is no-one holy [Or no Holy One] like the LORD;
there is no-one besides you; there is no Rock like our God.
2 Samuel 22:2 He said: "The LORD is my Rock , my fortress and my deliverer;
2 Samuel 22:3 my God is my Rock , in whom I take refuge, my shield and the
horn [Horn here symbolises strength.] of my salvation.
He is my stronghold, my refuge and my saviour from violent men you save me.
2 Samuel 22:32 For who is God besides the LORD? And who is the Rock except our God?
2 Samuel 22:47 "The LORD lives! Praise be to my Rock ! Exalted be God, the Rock , my Saviour!
2 Samuel 23:3 The God of Israel spoke, the Rock of Israel said to me:
'When one rules over men in righteousness, when he rules in the fear of God,
Psalm 18:31 For who is God besides the LORD? And who is the Rock except our God?
Psalm 18:46 The LORD lives! Praise be to my Rock ! Exalted be God my Saviour!
Psalm 19:14 May the words of my mouth and the meditation of my heart
be pleasing in your sight, O LORD, my Rock and my Redeemer.
Psalm 42:9 I say to God my Rock , "Why have you forgotten me? Why must I go about mourning, oppressed by the enemy?"
Psalm 78:35 They remembered that God was their Rock , that God Most High was their Redeemer.
Psalm 89:26 He will call out to me, `You are my Father, my God, the Rock my Saviour.'
Psalm 92:15 ..... "YHvH is upright; he is my Rock , and there is no wickedness in him."
Psalm 95:1 Come, let us sing for joy to the LORD; let us shout aloud to the Rock of our salvation.
Psalm 144:1 Praise be to the LORD my Rock , who trains my hands for war, my fingers for battle.
Habakkuk 1:12 O LORD, are you not from everlasting? My God, my Holy
One, we will not die. O LORD, you have appointed them to
execute judgment; O Rock , you have ordained them to punish.