John 14:26
"The Advocate, the Holy Spirit that the Father will send in my name--he will teach you everything and remind you all that [I] told you."
The first verse that was ever shown to me, questioning Sola Scriptura was 1 Timothy 3:15 "but if I should be delayed. you should know how to behave in the household of God, which is the church of the living God, the pillar and foundation of truth." This verse was enough for me to understand that the Bible clearly shows us that The church is necessary for us to hold onto the faith and preserve the faith. I was listening to some protestant radio show today who quoted John 14:26, and he was talking about the hope that we should have in Christ's words. It hit me like a lightning bolt that the verse that he quoted marries with the 1 Timothy verse. Christ told us that the Holy Spirit would teach us everything, and remind us of EVERYTHING that Christ told us. Obviously everything Christ said can not be recorded in the Bible, and we know that the Holy Spirit came to the disciples on the Day of Pentecost. It is so clear that the Church is an earthly institution given to us by God to help us not go astray.
I dunno maybe this makes sense to someone else, my mind is just bursting in awe right now.