Analysis of information sources in references of the Wikipedia article "Bí tích" in Vietnamese language version.
The Old Catholic Church accepts seven sacraments, the intermediaries of salvation.
The Augsburg Confession drawn up by Melanchton, one of Luther's disciples admitted only three sacraments, Baptist, the Lord's Supper and Penance. Melanchton left the way open for the other five sacred signs to be considered as "secondary sacraments". However, Zwingli, Calvin and most of the later Reformed tradition accepted only Baptism and the Lord's Supper as sacraments, but in a highly symbolic sense.
In the first place I deny that the sacraments are seven in number, and assert that there are only three, baptism, penance, and the Lord's Supper, and that all these three have been bound by the Roman Curia in a miserable captivity and that the Church has been deprived of all her freedom.