Keeping the commandments of God as per James indicates showing faith does not mean the 'revival' of the sacrificial system and related laws --- these were the ones (including related sabbaths but not 'the Sabbath') that were the 'bondage of the law' done away with as mentioned by Paul...
The 10 commandments in particular, reflect the Character of God. They are NOT BONDAGE, but FREEDOM...they are 'eternal principles' that will always exist - for without them there would be no fairness nor order --- this is what as I see it King David 'meditated on' when in the he bible says:
Psa 119:97 O how I love Your law! It is my meditation all the day.
Psa 119:98 Your commandments make me wiser than my enemies, For they are ever mine.
Psa 119:99 I have more insight than all my teachers, For Your testimonies are my meditation.
I don't believe he was 'meditating' on a bunch of rules and regulations that were 'bondage' as some put it, but understood how they reflected the Character and Nature of God...
In addition, regarding diet, the bible does speak of the New heaven and earth keeping the Sabbath day by 'all flesh' coming before Him, and that no-one that eats anything 'unclean' including swine or rat will come before Him...
Isa 66:17 "Those who sanctify and purify themselves to go to the gardens, Following one in the center, Who eat swine's flesh, detestable things and mice, Will come to an end altogether," declares the LORD.
Isa 66:22 "For just as the new heavens and the new earth Which I make will endure before Me," declares the LORD, "So your offspring and your name will endure.
Isa 66:23 "And it shall be from new moon to new moon And from sabbath to sabbath, All mankind will come to bow down before Me," says the LORD.
Clearly, this shows the Heart of God, and what He wants, and intends for Eternity with Him; so why go against that, and claim that the man Paul has given everyone 'license' to go against Gods Will and Desire for humanity - rather than what It 'truly is' --- even to the point of Eternity...