True they were commanded not to go the way of the Gentiles yet
Mat 10:5These twelve Jesus sent forth, and commanded them, saying, Go not into the way of the Gentiles, and into any city of the Samaritans enter ye not:
Its also shows they didnt understand the parable of what went into their mouth either because they were already eating with "unwashed hands" so he didnt really need to explain to them that they needed to wash them.
Mark 7:18 And he saith unto them, Are ye so without understanding also? Do ye not perceive, that whatsoever thing from without entereth into the man, it cannot defile him; Because it entereth not into his heart, but into the belly, and goeth out into the draught, purging all meats?
1Cr 6:12 All things are lawful unto me, but all things are not expedient: all things are lawful for me, but I will not be brought under the power of any.
1Cr 6:13 Meats for the belly, and the belly for meats: but God shall destroy both it and them.
Heb 9:10 Which stood only in meats and drinks, and divers washings, and carnal ordinances, imposed on them until the time of reformation.