Right out of the gate, Mr Martin fails the test of a true prophet of God as Mr Martin does what every trained false prophet does, he stops right before the conclusion of the matter which reveals the truth.
Act 15:21 For Moses has had throughout many generations those who preach him in every city, being read in the synagogues every Sabbath."
James clearly reveals here that it is on the 7th day Sabbath that those in Galatia would hear the truth, learn the truth in order to walk the truth. The Word of God put on flesh as our example of how to walk without sin and without deceit in our mouths just as He did.
1Pe 2:21 For to this you were called, because Christ also suffered for us, leaving us an example, that you should follow His steps: 22 "WHO COMMITTED NO SIN, NOR WAS DECEIT FOUND IN HIS MOUTH"; ... 25 For you were like sheep going astray, but have now returned to the Shepherd and Overseer of your souls.
Eze 22:26 Her priests have violated My law and profaned My holy things; they have not distinguished between the holy and unholy, nor have they made known the difference between the unclean and the clean; and they have hidden their eyes from My Sabbaths, so that I am profaned among them.
Eze 20:12 Moreover I also gave them My Sabbaths, to be a sign between them and Me, that they might know that I am the LORD who sanctifies them. 13 Yet the house of Israel rebelled against Me in the wilderness; they did not walk in My statutes; they despised My judgments, 'which, if a man does, he shall live by them'; and they greatly defiled My Sabbaths. Then I said I would pour out My fury on them in the wilderness, to consume them. 14 But I acted for My name's sake, that it should not be profaned before the Gentiles, in whose sight I had brought them out.23 “Also, I Myself lifted My hand in an oath to those in the wilderness, to scatter them among the gentiles and disperse them throughout the lands, 24 because they had not done My right-rulings, and they rejected My laws, and they profaned My Sabbaths, and their eyes were on their fathers’ idols. 25 “And I also gave them up to laws that were not good, and right-rulings by which they would not live."
Heb 4:2 For indeed the gospel was preached to us as well as to them; but the word which they heard did not profit them, not being mixed with faith in those who heard it. 3 For we who have believed do enter that rest, as He has said: "SO I SWORE IN MY WRATH, 'THEY SHALL NOT ENTER MY REST,' " although the works were finished from the foundation of the world. 4 For He has spoken in a certain place of the seventh day in this way: "AND GOD RESTED ON THE SEVENTH DAY FROM ALL HIS WORKS"; ... 9 There remains therefore a rest for the people of God. ... 12 For the word of God is living and powerful, and sharper than any two-edged sword, piercing even to the division of soul and spirit, and of joints and marrow, and is a discerner of the thoughts and intents of the heart. 13 And there is no creature hidden from His sight, but all things are naked and open to the eyes of Him to whom we must give account.
Act 5:29 But Peter and the other apostles answered and said: "We ought to obey God rather than men. 30 The God of our fathers raised up Jesus whom you murdered by hanging on a tree. 31 Him God has exalted to His right hand to be Prince and Savior, to give repentance to Israel and forgiveness of sins. 32 And we are His witnesses to these things, and so also is the Holy Spirit whom God has given to those who obey Him."
The first part of the His fruit is love. Love is defined as obedience towards all that God gave mankind to obey in order to be a special treasure to Him, a royal priesthood under the authority of the High Priest, our Master Yeshua Messiah. If the High Priest is the Master of the Father's seventh day Sabbath, then as special treasures of a royal priesthood to God the Father, then it only makes sense that we His royal priesthood would show up for duty on His day to do His good works.
Eph 2:10 For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand that we should walk in them.
Tit 2:13 looking for the blessed hope and glorious appearing of our great God and Savior Jesus Christ, 14 who gave Himself for us, that He might redeem us from every lawless deed and purify for Himself His own special people, zealous for good works.
Mat 5:16 Let your light so shine before men, that they may see your good works and glorify your Father in heaven. 17 "Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill. 18 For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled. 19 Whoever therefore breaks one of the least of these commandments, and teaches men so, shall be called least in the kingdom of heaven; but whoever does and teaches them, he shall be called great in the kingdom of heaven. 20 For I say to you, that unless your righteousness exceeds the righteousness of the scribes and Pharisees, you will by no means enter the kingdom of heaven.
Act 15:21 For Moses has had throughout many generations those who preach him in every city, being read in the synagogues every Sabbath."
Indeed, notice what the text states, that Moses was being read in the synagogues every Sabbath - not the churches which are shown coming together to break break upon the beginning of the 1st day, and having service then. (Acts 20:7) And considering the cardinal importance that you see sabbath keeping having, it is incongruous that this command be not manifestly affirmed under the new covenant.
Indeed, your entire post utterly fails to provide what is desperately needed, that of any reiteration or repetition of the 4th commandment under the new covenant, yet the other 9 are, while the only teaching under the new covenant is that which refers to the sabbath or sabbath days being a shadow of things to come, (Col 2:16) a rest which typifies what believers gain by faith, )Heb. 4) or any record of the disciples specifically having meetings on the 7th day, while they specifically met more than once on the 1st day, as shown.
Do you believe all those who do not keep the 7th day commandment, once told, are lost?