St Paul was talking about those who wrongly taught that Christians should ordinarily never eat meat or ordinarily never eat the meat of certain species of animals, for instance, like the prohibition against eating pork and the meat of other “unclean” animals that was part of the Mosaic Law. He was not talking about the occasional day of abstinence from meat as practiced by Catholics as a form of penance. Think of the Catholic disciplinary practice as a modified fast, a fast from meat. Jesus said his disciples would fast once he was taken away. (Matthew 9:15)
this is a sticking point: So Christ died fulfilled the old law of Moses, took it out of the way, and then new ceremonial laws were established? So verse 16 applies to keeping mosaic festivals and kosher, but catholic festivals and food rules are obligatory?
There is also, Roman’s 14:5-12, which seems to not be about Moses at all. This passage says holy days are a matter of private conviction. Is this a case of pastoral council that can be changed?
The sheer volume of knowledge needed to comply with canon law actually seems daunting. “Take my yoke upon you and learn of me, for my yoke is easy and my burden is light.”
Romans 14:5-12Douay-Rheims 1899 American Edition (DRA)
5 For one judgeth between day and day: and another judgeth every day: let every man abound in his own sense.
6 He that regardeth the day, regardeth it unto the Lord. And he that eateth, eateth to the Lord: for he giveth thanks to God. And he that eateth not, to the Lord he eateth not, and giveth thanks to God.
7 For none of us liveth to himself; and no man dieth to himself.
8 For whether we live, we live unto the Lord; or whether we die, we die unto the Lord. Therefore, whether we live, or whether we die, we are the Lord’s.
9 For to this end Christ died and rose again; that he might be Lord both of the dead and of the living.
10 But thou, why judgest thou thy brother? or thou, why dost thou despise thy brother? For we shall all stand before the judgment seat of Christ.
11 For it is written: As I live, saith the Lord, every knee shall bow to me, and every tongue shall confess to God.
12 Therefore every one of us shall render account to God for himself.