Concerning what every Catholic should know:
Whose word is truth?
First, that quote from Canon does not say anything about Scripture. All it says is the Pope has infallible teaching authority. If the Pope has infallible teaching authority, this is granted by God, not by men.
The actual quote from Matt 4:4 and 2Tim 3:16 do not contradict the infallibility doctrine. All the quote from Mark means is that true Tradition cannot contradict the Word of God. In reference to the Pope, this means that what he infallibly teaches cannot contradict the Word of God, not that he cannot contradict your interpretation of it.
Catholics do not worship sacred images; veneration is not worship. And Catholics do not bow down before sacred images. There is a difference between bowing down before, and bowing down in front of. The earlier one implies that it is because of the image that we bow; the latter implies that it is because of what the image represents. When a Catholic bows in front of a statue of Jesus, we are bowing because of Jesus, not the statue. Jesus does not have one nature with the statue. When interpreting commands in Torah, be careful, as there is a command in Torah that prohibits eating cheeseburgers; however, because of how it is worded and what it fully prohibits, it comes across as a moral, not ritual, commandment. If you want to claim that the Catechism of the Catholic Church incorporates Ex 20:4-5, fine, but keep in mind it is under the subheading of “Love the Lord thy God”. As we are not worshiping the sacred art, I am uncertain of how the Sacred Art is a failure to Love God.
Sacrifice: Whoever wrote that has clearly failed to read those passages in the context of what surrounds them. Also, we agree there is one sacrifice. The Eucharistic Celebration in Mass is not redoing the sacrifice. The Body and Blood in Mass is the same Body and the same Blood in the original Sacrifice. How do you intend to explain 1 Cor 11:27-32? This gives credence to the Catholic belief that one should be in a state of Grace before partaking in Communion. Paul says that Jesus said, “This chalice is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me.”
In addition Paul concludes 1 Cor 11 with a statement he will give more directions when he comes. What directions did he give? Since he has books in the Bible, what he said there must carry weight.
Priests:
Concerning 1 Peter 2:9, this is almost a direct quote of Ex 19:6. In this one God tells the Israelites that they will be to him a Kingdom of priests. However, not every single Israelite is/was a priest. The first requirement to be a priest was to be a Levite, and not every Israelite was a Levite. Going back to 1 Cor and examing 12:1-31, we see that Paul states we are all one body, but each of us has a different function within that body.
1 Tim 2:5 only says there is one mediator; it does not deny the possibility of subordinate mediators. When we examine Hebrews 5,6, and 7, Paul repeatedly refers to Jesus as the new High Priest. He does not explicitly mention what happened to the lower priests. While it is clear that Jesus is the High Priest in the Order of Melchizedek, it is unclear if there can be subordinate priests. However, we have a curious statement in Hebrews 7:25, Jesus “lives to make intercession for them.” Where else do we see intercessions made? In 1 Tim 2:1, Paul requests that intercessions be made (amongst other things for a list of people). Someone is supposed to imitate Christ by interceding.
Baptism/Salvation:
In Acts, we have several baptisms. In Acts 9:18, Paul is baptized. There is no statement as to how or with what. So we will backtrack to Acts 8:26-39. Phillip converts an Ethiopian Eunuch. While talking with the Eunuch, they come upon some water and the Eunuch asks if he can be baptized. Both Phillip and the Eunuch go down to the water and the Eunuch is baptized with the water. However, I suppose this is not enough, but I cannot find a passage that says the water is unnecessary. When Jesus was baptized, it was with water.
And whoever wrote this has taken Romans 11:6 out of context. The beginning of Romans 11 makes it clear that Paul is talking about the Jews. He then proceeds to say that there is a remnant chosen by Grace and the choice is no longer done because of Works. This is clearly referring to the Jewish sacrifices in the Temple. It is likely that anywhere else it denies the necessity of Works, it is a denial of Works of the Law.
If you want an example of where Paul speaks highly of Baptism as a work the attains justification, examine Romans 6:3. Here he says that we are baptized into Jesus. From this, we are baptized into his death and resurrection.
The actual word “baptize” means to immerse in water. Acts clearly showed those who believed, born of the Spirit were then baptized.
It is interesting to clearly note the sequence of “events” in Acts 10 at Cornelius’ house. Peter preached the Gospel of Christ crucified, buried and three days later resurrected and now seated at the right Hand of The Father. Those assembled clearly had hearts prepared and repentant because after hearing they were filled with The Holy Spirit and then were baptized.
I think the sequence is telling. I will note even before Peter arrived we are told God looked favorably on Cornelius (he was seeking God) and God moves the necessary people (Peter) for Cornelius and others to receive the Gospel. An excellent NT example of the OT truth of God chooses and those He chooses are usually seekers of Him.