@Xeno.of.athens My dear friend, I am numbering the items on your list, so that I can remark on what is essential, unessential, or indeed where the opposite is essential: Finally at the end i give my opinion on what can be regarded as subject to liberty under this supposedly Augustinian quote.
1. Not only is it nonessential, but actually worshipping in a church that is intentionally iconoclastic is spiritually harmful. We know from archaeology at Dura Europos and from the Old Testament itself that both Judaism and early Christianity had iconography, and we know the history of Iconoclasm from the late Byzantine Empire, where it was essentially adopted by superstitious generals and politicians who wished to pass the buck for their inability to defend Egypt and Syria from conquest by the Ummayid Conquest. Martin Luther did not revive it, but rather others in the Reformation brought it back after centuries of abeyance, and the result was the destruction of much of the priceless cultural heritage in Northern Europe (however the Counter-Reformation would cause even more because of the decision of the Council of Trent to remove most rood screens from churches in Europe in favor of an open view of the apse such as one found in a Franciscan or Dominican church, and these rood screens or chancel screens were literally the Western version of the Iconostasis, both being derived from the Templon, for example, at Hagia Sophia in Constantinople (Rood being an old word for Crucifix).
2. It is essential to be baptized as an infant, and the sacrament is a means of grace and is regenerative, although if one becomes confused about this during their adulthood, after having been previously baptized, well, I pray for the salvation of everyone and there is also even the issue of someone being in a fully orthodox church but having an incorrect understanding of the sacrament.
3. No, rather it is essential that you acknowledge they are the Body and Blood of our Lord, as per 1 Corinthians 11:27-32, which was deleted from the Lectionary of the Novus Ordo Missae on Maundy Thursday (at some point I’m going to write a friendly reply to your thread in Traditional Theology about the New Mass and some specific reasons why I think the TLM attracts people).
4. No, rather, you should believe as your church along with the Orthodox, the Roman Catholics, the Church of the East, the Lutherans and some other churches such as Old Catholics and Anglo Catholics teach, with minor variations, that the Gifts become the actual Body and Blood of our Lord during the Eucharist, for the same reasons as no. 3.
5. The Old Testament canon was never formally settled and the Eastern Orthodox, Roman Catholics and Anglicans have slightly different numbers of books, and also there are differences between the contents of the Septuagint as included in Greek Orthodox Bibles and the contents of the Church Slavonic Old Testament, which is translated from the Septuagint; additionally there are the books in the Ethiopian canon. I think anything used by the Ethiopians can be regarded as being at least deuterocanonical and anything used in the Vulgate or the Orthodox versions of the Septuagint can be regarded as protocanon. Indeed I would argue, as have some Orthodox theologians, that if we were to evaluate the importance of books by how often they are quoted in the liturgy, that some “Deuterocanonical” or “Apocryphal” books are actually more important than some books from the 66 book Masoretic canon. Even the book of Numbers comes to mind as one that is perhaps eclipsed by Wisdom or Ecclesiasticus or Tobit or the Longer Versions of Daniel and Esther.
6. No
7. No
8. Keeping the Seventh Day holy requires remembrance of Christ reposing in a tomb for us on that day, which is why the Orthodox celebrate the Vesperal Divine Liturgy and baptize catechumens on Holy Saturday, and at other times in Lent and Pre Lent and also before Pentecost have Soul Saturdays, which are like requiem masses, not unlike All Souls Day in the Roman church, on those Saturdays, for the same reason. In the Byzantine Rite of the Eastern Orthodox church, and similar patterns exist in the Oriental Orthodox churches, there is a default theme to each day of the week, with Sunday commemorating the resurrection, Wednesdays and Fridays commemorate Christ's suffering and crucifixion, and then to quote the
OCA website that summarized the other days more easily than I would have, “Monday's theme is the “bodiless powers”the angels. Tuesday is dedicated to the memory of John the Baptist, Thursday to the apostles and Saint Nicholas, and Saturday to the Theotokos with the memory of the departed.” I believe that the Liturgy of the Roman Church historically met this criteria with the celebration of the Paschal Vigil Mass on Easter Even ( Holy Saturday ) with a very similar set of Old Testament lessons to those used by the Orthodox (12 minimum vs. 14 minimum in the Orthodox), but then Pope Pius XII made ill advised changes to the Paschal Triduum including moving the Paschal Vigil to later in the day, but insofar as it still starts at Vespers it still begins on Holy Saturday (Vespers or Vigils services have the effect of advancing the liturgical clock - in recognition of this at Russian, Ukrainian and Bulgarian and American Orthodox churches of Slavic heritage, on Holy Saturday the black paraments are taken down midway through the vesperal liturgy and replaced with Paschal white paraments, and the clergy will change their vestments from black to Paschal white. Some Russian churches, but usually not ROCOR (Russian Orthodox Church Outside Russia) will then change vestments again in between Paschal Matins which traditionally begins at or shortly before midnight and the Paschal Divine Liturgy, from white to red. This is interesting because the reverse happens at the Feast of the Nativity, since red vestments are commonly worn in Advent.
9. Our Lord, God and Savior Jesus Christ, has summarized the commandments as “Love God with all your Heart, Mind and Soul” and “Love your neighbor as yourself” and we must confess our failures to do these two things and seek to repent of them. This life was given to us for repentence.
10. The Word of God is Jesus Christ, although the Bible is a verbal icon of Christ, revealing Him in the same way that He reveals the Father, but calling it the Word of the Word is problematic because it would deny the deity of Jesus Christ. One concern I have about the Western Church as a whole is inadequate references to the deity of Jesus Christ in prayer and worship; from the worship of many churches one might be led to believe that Christ was merely the Son of God but not God Himself, the false doctrine of Arianism. This is why I endorse the Orthodox approach that stresses the deity of Christ.
11. If the church teaches the orthodox faith of the One Holy Catholic and Apostolic Church, yes. The main freedom, the area where in non-essentials, liberty exists, is in terms of liturgical rite, just as thee are multiple liturgical rites in the Roman Catholic Church, the Eastern Orthodox Church (where there are multiple major variants of the Byzantine Rite such as the Russian Old Rite, the Sabaite-Studite Typikon, the Violakis Typikon, and also there are the Western Rite parishes), the Oriental Orthodox, which has four main liturgical rites (Syriac, Coptic, Armenian and Ethiopic) used in some cases by multiple churches (four autocephalous Armenian jurisdictions, which is a relic of the period when there were two Armenian kingdoms at the same time, that of Armenia proper and that of Cilicia, which were allies of the Byzantine Empire guarding it from invasion from Muslims in the East), two using the Syriac liturgy, the Syriac Orthodox and the Malankara Orthodox, and two using the Ethiopic liturgy, the Ethiopian Tewahedo Orrthodox Church and the Etirean Tewahedo Orthodox Church.
One nice thing about the Roman Catholic Church is that it celebrates in more of the historic liturgical rites than any other church, albeit unfortunately some of the liturgical rites were modified before Vatican II and later determinations of the Orthodoxy of their denominations, for example, the Syriac Orthodox and Chaldean and Syro Malabar Catholic liturgies, and others were modified both before and afterwards in deleterious ways (such as the Maronite liturgy), although some aspects of the post Vatican II change to the Maronite liturgy, such as cycling through the Eucharistic prayers, I like, the disuse of so many such as that of Peter (Sharar), a particularly loved anaphora, and also the obliteration of the beautiful flowery character of the prayers that characterized the West Syriac Rite as a unifying feature of Maronite, Syriac Orthodox and Syriac Catholic churches in the name of “simplification”, but the real problem has been the failure of most Maronite churches to preserve their traditional music. I would say the Maronite Rite in some respects has been more substantially adversely impacted than the Roman Rite or the Ambrosian RIte by the liturgical changes.