well, I can take a quick run at this.
Yes, the pope was the ruler of the Church. All rule was monarchical in those days–that was the political and social structure which gave order to the disorder following the Roman collapse. There was no democracy or republicanism in those days, remember. It’s useful to not impose our modern historical sense upon the past.
decrees were issued by medieval popes declaring all apostles to have been submitting to the authority of St Peter as first popes & that it’s heresy to think otherwise.
I don’t know about particular decrees, but as the apostles did submit to the authority of Peter as to their leader, what would be wrong about decreeing so. See all the voluminous biblical support for Peter being the first always when there is a full group of apostles; see Jesus Christ’s several special conversations with Peter; see how John deferred to Peter at the empty tomb; and the way Peter ended the dogmatic part of the debate at the First Council; then the way the eastern church deferred to Rome even though a living first Apostle, John was nearer, etc.
Then he gives arguments with biblical & patristic quotes for the apostles being equal in authority,
Here’s the Catholic understanding: All the apostles together exercise Christ’s authority when they act as one body. They couldn’t do it without Peter. But he could act without them, on his own, with that authority. See the places in the NT where Peter alone is directly and solely given the authority; and where that authority is also separately given to the united body of the twelve. As with so many Catholic answers, it is both/and, not either/or.
for the ‘Rock’ of Matt 16 to have been Peters confession
This is an old chestnut for Protestantism; I see it would also be a problem for the Eastern Orthodox. They both must have it this way, otherwise their rejections of Peter haven’t a pebble to stand on. But that biblical interpretation fails. Look into the issue more and you will see. One quick clarifier is to understand that Jesus and His apostles spoke in Aramaic to each other. In Aramaic we have Jesus saying to Peter, “You are Cepha, and upon this cepha I will build my church.” Just skip the Latin.
Patriarch of Rome was only 1st among equals
cute. He was first, and the servant of the servants. He is the first servant, if you will!
His doubts began when he found a decree by Pope Innocent X that declared everyone who believed St Paul was not under St Peters papal authority to be anathema. (Sanctii Officii, 1647)
We can see Paul under Peter’s authority in the NT. Anathema means excommunicated. In these democratic days we cannot seem to even consider it. We only accept self-excommunication these days: if, for example, you commit an abortion, you are automatically self-excommunicated. It means you have committed a mortal sin, God is no longer living in you, and you are therefore de facto not in unity with the body. You are outside the body. So repent, confess, and you will be inside the body again.
You read this man’s book. Now give equal time and read a book or books giving the true and Catholic side of these issues. You can have a field day. But study is indicated. May I suggest you read the tracts available on this website as a start, also go to the websites of the Catholic Answers radio speakers, also study at EWTN …