Funny about that.....
When I saw someone post that ridiculous statement, I almost fell out of my chair. It WAS stupid, and I don't think that person got any support from anyone. I have not seen it lately, but as I said before, we've got your 6.
"No one shall pray in common with heretics and schismatics" - Council of Laodicea. The 1917 Code of Canon Law states: that: " It is not permitted at all for the faithful to assist in any active manner at or to have any part in the worship of non-Catholics." [Canon 1258]
MORTALIUM ANIMOS: 10. So, Venerable Brethren, it is clear why this Apostolic See has never allowed its subjects to take part in the assemblies of non-Catholics: http://www.vatican.va/holy_father/pius_xi/encyclicals/documents/hf_p-xi_enc_19280106_mortalium-animos_en.html
Is it permitted for Christians to be present at, or to take part in, conventions, gatherings, meetings, or societies of non-Catholics which aim to associate together under a single agreement everyone who, in any way, lays claim to the name of Christian? In the negative! - (Pope Pius XI, Mortalium Animos)
How does a Catholic sin against faith? A Catholic sins against Faith by Apostasy, heresy, indifferentism and by taking part in non-Catholic worship." (Catechism of the Council of Trent, and the Baltimore Catechism)
Rome, Italy, Feb 19, 2010 / 02:03 pm (CNA).- The president of the Pontifical Council for Promoting Christian Unity, Cardinal Walter Kasper, announced this week that Pope Benedict XVI will visit the Evangelical Lutheran Church located in Rome on March 14 for an ecumenical celebration.
UNITATIS REDINTEGRATIO: In certain special circumstances, such as the prescribed prayers "for unity," and during ecumenical gatherings, it is allowable, indeed desirable that Catholics should join in prayer with their separated brethren. Such prayers in common are certainly an effective means of obtaining the grace of unity, and they are a true expression of the ties which still bind Catholics to their separated brethren. "For where two or three are gathered together in my name, there am I in the midst of them". - http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_decree_19641121_unitatis-redintegratio_en.html
Canon 229 §1. Lay persons are bound by the obligation and possess the right to acquire a knowledge of Christian doctrine adapted to their capacity and condition so that they can live in accord with the doctrine, announce it, defend it when necessary, and be enabled to assume their role in exercising the apostolate.
APOSTOLICAM ACTUOSITATEM POPE PAUL VI ON NOVEMBER 18, 1965, Since, in our own times, new problems are arising and very serious errors are circulating which tend to undermine the foundations of religion, the moral order, and human society itself, this sacred synod earnestly exhorts laymen-each according to his own gifts of intelligence and learning-to be more diligent in doing what they can to explain, defend, and properly apply Christian principles to the problems of our era in accordance with the mind of the Church.
GAUDIUM ET SPES, 28. Respect and love ought to be extended also to those who think or act differently than we do in social, political and even religious matters. In fact, the more deeply we come to understand their ways of thinking through such courtesy and love, the more easily will we be able to enter into dialogue with them. -http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_const_19651207_gaudium-et-spes_en.html