Hi, Mountaintop,
Welcome to CAF!
I think you will find this list to be an on-going source of faith and inspiration.
You have made an excellent observation and one that truly deserves to be acknowledged for clearly stating what it was that took place in Matthew 16.
There are those who go to great lengths to either ignore or minimize elements in the Bible that they really do not agree with - but, they really can’t say that! So, they interpret it out of both true meaning and existence.
We have God the Father selecting Peter - and - giving him the answer to Christ’s question on “Who do men say I am?” Peter was truly hand-picked by God to lead the Church.
We have God the Son identifying what His Father had done - and then stating that He was building His Church - and, doing so on this truly sinful, bragging and loud-mouthed man!!
And, just in case there some some confusion … Christ gives Peter the Keys to bind and lose - both on earth and heaven. There were not 12 sets of keys … only one set!
Peter remained a sinful man - but, a man who really wanted to follow Christ…but, in his own way! In the next verse, Peter chides Christ for ‘scaring the boys’ with talk about dying in Jerusalem. And, what does Christ call the head of His Church - a devil!

This is most telling in that we see Christ will demonstrate the Power of God by using the weak and not the strong. Nothing basic has changed - just the degree to which we sin. In the First Century it was not possible to abort millions of unborn babies, have devious bishops look the other way at Catholic politicians who encourage, promote and vote for abortion, have the capacity to kill millions of people with a nuclear weapon, have a few devious priests sexually abuse many children or manipulate securities so that millions of people lost many millions of dollars! We have come a long way!
Today the Catholic Church is in crisis. We have the choice today of responding like St. Catherine of Siena or Martin Luther - it is really in our hands if and how we respond to the Grace of God to help move the Church of Christ (and, that would be the Catholic Church) ever closer to Christ.
God bless