I’m not sure if you’re looking for an immediate time sensitive answer. But here is a shorthand response that I can give as a starting point.
I believe the scripture this person is referring to is:
Matthew 16:16-19 King James Version (KJV)
16 And Simon Peter answered and said, Thou art the Christ, the Son of the living God.
17 And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven.
18 And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.
19 And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven.
Response to “This Rock”
"…Protestants generally have thought that it refers to Peter in his role of confessing Jesus as the Messiah, and that the other disciples would share in that role as they made a similar confession (see Eph. 2:20, where the church is built on all the apostles; cf. Rev 21:14)…"ESV Study Bible.
Also, another reference about Christ being the “rock”:
1 Corinthians 10:4 King James Version (KJV)
4 And did all drink the same spiritual drink: for they drank of that spiritual Rock that followed them: and that Rock was Christ.
Response about Binding and Loosing
“Peter also has authority to exercise discipline concerning right and wrong conduct for those in the kingdom, an authority that is not exclusive to Peter but is extended to the church as a whole in Matt. 18:18; cf John 20:23. Jesus delegates authority to human leaders in the church who are called to govern his church on earth, under his ultimate authority, through the application of his Word.” ESV Study Bible
"Yeshua gave Shimon Kefa (Simon Peter) the keys, or the authority, to bind and loose concerning scriptural questions within the early Messianic Community, an authority in all likelihood shared by others of the apostolic circle (cf. John 20:23). " The Complete Jewish Study Bible
John 20:19-23 King James Version (KJV)
19 Then the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled for fear of the Jews, came Jesus and stood in the midst, and saith unto them, Peace be unto you.
20 And when he had so said, he shewed unto them his hands and his side. Then were the disciples glad, when they saw the Lord.
21 Then said Jesus to them again, Peace be unto you: as my Father hath sent me, even so send I you.
22 And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Ghost:
23 Whose soever sins ye remit, they are remitted unto them; and whose soever sins ye retain, they are retained.
The “rock” is a reference to Jesus being the Messiah, and “binding and loosing” is an authority that was given to the church as a whole.