Jesus is not the “Master” — are you Christian? Surely you know that he considers the disciple a friend (cf. John 15:15). This is not the Old Testament situation, so it escapes your notice, perhaps.
All purity rules in the OT surround the holy space of the Temple, and they are very involved. Why don’t you follow any of those rules?
Oh, because there’s no Temple. Another problem you decide not to deal with.
Gentile people were never under the law, and could never approach the Temple. It was forbidden. If you are holding yourself to Jewish law, then you are outside the covenant community.