There is no requirement in Scripture that the individual believer must follow some earthly organization that fancies itself to be Christ’s true church here on the earth.
The teachings of the Church, verified by both Scripture and Tradition are to be found in the teachings of the bishops, ratified by the Pope. Many, including priests and nuns and even popes do not preach or live those teachings. It is up to each of us to know and live those teachings. Any way all institutions have their scoundrels. God will judge us all.
Then you can provide the Scripture to support the claims of the apparition claiming to be Mary regarding this:
“ Whosoever dies clothed in this Scapular shall not suffer eternal fire.”
http://www.fatima.org/apostolate/pdf/brown_scapular.pdf
It still doesn't prove the Catholic church is the church to which Jesus was referring.
And the rock is not Peter but Jesus Himself, and Scripture tells us that.
Peter – rock
Matthew 16:18 - http://bible.cc/matthew/16-18.htm
Jesus said that Peter was *petros*(masculine) and that on this *petra*(feminine) He would build His church.
Greek: 4074 Pétros (a masculine noun) – properly, a stone (pebble), such as a small rock found along a pathway. 4074 /Pétros (”small stone”) then stands in contrast to 4073 /pétra (”cliff, boulder,” Abbott-Smith).
“4074 (Pétros) is an isolated rock and 4073 (pétra) is a cliff” (TDNT, 3, 100). “4074 (Pétros) always means a stone . . . such as a man may throw, . . . versus 4073 (pétra), a projecting rock, cliff” (S. Zodhiates, Dict).
4073 pétra (a feminine noun) – “a mass of connected rock,” which is distinct from 4074 (Pétros) which is “a detached stone or boulder” (A-S). 4073 (pétra) is a “solid or native rock, rising up through the earth” (Souter) – a huge mass of rock (a boulder), such as a projecting cliff.
4073 (petra) is “a projecting rock, cliff (feminine noun) . . . 4074 (petros, the masculine form) however is a stone . . . such as a man might throw” (S. Zodhiates, Dict).
Paul tells us here who the rock- petra- iis.
1 Corinthians 10:1-4 For I do not want you to be unaware, brothers, that our fathers were all under the cloud, and all passed through the sea, and all were baptized into Moses in the cloud and in the sea, and all ate the same spiritual food, and all drank the same spiritual drink. For they drank from the spiritual Rock (petra) that followed them, and the Rock (petra) was Christ.
And Peter himself tells us here.
1 Peter 2:1-8 So put away all malice and all deceit and hypocrisy and envy and all slander. Like newborn infants, long for the pure spiritual milk, that by it you may grow up into salvation— if indeed you have tasted that the Lord is good.
As you come to him, a living stone rejected by men but in the sight of God chosen and precious, you yourselves like living stones are being built up as a spiritual house, to be a holy priesthood, to offer spiritual sacrifices acceptable to God through Jesus Christ. For it stands in Scripture: “Behold, I am laying in Zion a stone, a cornerstone chosen and precious, and whoever believes in him will not be put to shame.”
So the honor is for you who believe, but for those who do not believe,
“The stone that the builders rejected has become the cornerstone,”
and
“A stone of stumbling, and a rock (petra) of offense.”
They stumble because they disobey the word, as they were destined to do.
All occurrences of *petra* in the Greek.