Scripture itself teaches that the ceremonial precepts of the Mosaic Law have been abolished, set aside, and fulfilled in Christ, while the moral law remains. St Paul explicitly says the Old Covenant legislation was “set aside because of its weakness and uselessness” (Heb 7:18)
Heb 7:11-18 says the levitical priesthood is replaced by Christ's priesthood.
11 Now if
perfection was through the Levitical priesthood (for on the basis of it the people received the Law), what further need
was there for another priest to arise according to the order of Melchizedek, and not be designated according to the order of Aaron? 12 For when the
priesthood is changed, of necessity there takes place a change of law also. 13 For the one concerning whom these things are spoken belongs to another tribe, from which no one has officiated at the altar. 14 For it is evident that our
Lord was descended from Judah,
a tribe with reference to which Moses
spoke nothing concerning priests. 15 And this is clearer still, if another priest arises according to the likeness of Melchizedek, 16 who has become
such not on the basis of a law of physical requirement, but according to the power of an indestructible life. 17 For it is attested
of Him,
“Y
ou are a priest forever
According to the order of Melchizedek.”
18 For, on the one hand, there is a
setting aside of a former commandment because of its weakness and uselessness 19 (for the Law made nothing perfect), and on the other hand there is a bringing in of a better hope, through which we draw near to God. 20 And inasmuch as
it was not without an oath 21 (for they indeed became priests without an oath, but He with an oath through the One who said to Him,
“The Lord has sworn
And will not change His mind,
‘
You are a priest forever’”);
22 so much the more also Jesus has become the guarantee of a better covenant.
23 The
former priests, on the one hand, existed
in greater numbers because they were prevented by death from continuing, 24 but Jesus, on the other hand, because
He continues forever, holds
His priesthood permanently. 25 Therefore
He is able also to save forever those who draw near to God through Him, since
He always lives to make intercession for them.
26 For it was fitting for us to have such a high priest, holy, innocent, undefiled, separated from sinners and exalted above the heavens; 27 who does not need
daily, like those high priests, to offer up sacrifices, first for His own sins and then for the
sins of the people, because this He did
once for all when He offered up Himself. 28 For the Law appoints men as high priests who are weak, but the word of the oath, which came after the Law,
appoints a Son, made perfect forever.
Heb 7 says nothing about the "old covenant"
and that God “abolished in His flesh the law of commandments in ordinances” (Eph 2:15).
Eph 2 is talking about the ceremonies that separate Jewish Christians from gentile Christians. It has nothing to do with deleting commandments such as "do not take God's name in vain". Nor does it argue that it is only a sin when Jews take God's name in vain but not a sin if gentiles do it.
He also teaches that Christians are not under the Mosaic law (Rom 6:14)
Rom 13 and Rom 7 quote the Mosaic Law and state that all mankind are judged as sinners by the Law that Christ affirms in Matt 19 and in Eph 6:1-2 and in Rom 7 where the Law of Moses says "do not covet" and in Matt 22 where the Law of Moses says "Love God with all your heart" Deut 6:5 and "love your neighbor as yourself" Lev 19:18
and that the food laws in particular have been cancelled: “Let no one pass judgment on you in questions of food… these are a shadow… but the substance belongs to Christ” (Col 2:16–17). Christ Himself declared all foods clean (Mark 7:19)
Mark 7 is a dispute about eating BREAD bought in the market place. not meat. The issue is the customs of the Pharisees as Mark 7 points out. There is no OT rule about bread being "unclean".
You are taking things out of context
, and the apostles—under the Holy Spirit—refused to impose the Mosaic code on Gentile believers (Acts 15:28–29).
Acts 15:1-2 says the subject it about the invented idea of some Christians that gentiles had to be circumcised in order to be saved. The chapter rejects that teaching but it does not say that gentiles can ignore the commandments ... no one is argue that it is ok for gentiles to take God's name in vain but not ok for Jews.
You are taking the chapter out of context.
