Was this the immaculate conception? Where can I find any scripture that even remotely suggests that Mary was sinless?
The Church is a living body and does not stagnate in the 1st cent. That is what fundamentalists except, only a literalist understanding of Scripture. They imagine the 'voice' of God dictating to robotic listeners who then write exactly what was dictated to them. As such you have much in common with Catholic fundamentalists and their insistence on dogma written in stone. Neither take into account the moving forward of the Gospels themselves. Need only to compare Mk's image of Mary with Mt and Lk and especially Jn. There is a forward movement as to the understanding of Mary in the NT itself.
As I have previously stated, the Church makes no claim that all doctrine is worded in Scripture.
Until the 16th cent we pretty much were.
This is not the Christianity started by the Son of God.
The Church is greater than and not identified with a hierarchy.
Being that the Church is made up of human beings, and as such sinful, only through the Grace of God is it a community, for all its sinfulness, is at the same time holy and for all its holiness is at the same time sinful.
Augustine
Wherever in my books I have described Church as being without spot or wrinkle,
I have not meant to imply that it was already so, but that it would prepare itself to be so, at the time where it too will appear in its glory, In the present time, because of the inexperience and weakness of the members it must pray everyday anew; " Forgive us our trespasses.
Aquinas
That the Church will be glorious, without spot or wrinkle is the final goal to which we are led
through the sufferings of Christ. This will only be true in our eternal home, not as the way thither,for now we would deceive ourselves if we were to say we have no sin, as I John i:8 points out.
I repeat you have no knowledge of the Catholic Church.