To understand what most 'Messianic' disciples believe we need to understand that the Mosaic law consisted of 3 parts: Worship/God, health, and moral laws.
The worship/God laws included the 7 Biblical festivals (6 feasts and 1 fast), as well as the sacrificing of animals. The health laws included such things as not eating scavenger animals and washing your hands. The moral law included things like assigning responsibility if your cow injured my cow and repayment of debt.
All 3 parts of the law (God/health/moral) are found in and summarized in the 10 Commandments.
For instance, if you are having a friend over for dinner you won't serve an unclean animal (health), as honoring your neighbor (moral) who is made in the image of God. (God). Therefore all 3 parts (God/health/moral) are summarized in the 10 Commandments.
Paul's wrote of these 3 elements of the law in Romans 14 when he noted some choose to honor Sabbath days and some do not (God), that some eat only herbs, some eat all things, some drink wine and some don't (health), and he brought it all together by saying what each person does they do so unto the Lord, so walk in love towards one another and don't argue about it. (moral) Thus once again we see, walking in love fulfills the whole law because love includes all 3 parts of the law.
What is a Judaizer?
There were some in Paul's day who said the work of Jesus wasn't enough, and walking in love towards God and man doesn't fulfill the law. They believed we are made 'more complete' by obeying the 613 specific laws of Moses, or at least selective ones that applied.
Today when we talk of 'Messianic' believers, many of them follow in this same spirit. They believe just walking in love towards God and man isn't enough, we must also walk in the health and the part of the worship law that can be observed. Thus they often observe the 7 Biblical festivals, gather for worship on Friday night or Saturday, and often follow some of the dietary laws in addition to walking in love. (There is no Biblical command to worship each Friday night or Saturday, it is a man-made tradition created by the Pharisees roughly 200 BC. See Exodus 20:8-11 for the Sabbath command)
They fail to recognize what the founding apostles believed and taught as I pointed out above: All 3 parts of the Mosaic law are found within the 2 Royal laws: Love the Lord with all your heart, and your neighbor as yourself, which as Paul said, fulfills the whole law.
To teach that disciples are not complete or may become 'more complete' or 'please God more' if they specifically follow each Old Testament law, is wrong, possibly out of ignorance (though zealous) and more than that, heresy and rather a slap in the face of Jesus and His work on the cross. But many think they are walking in higher truth, though living in fear and bondage which is plain for all to see.
My experience has been in interacting with many is that fear is often the common denominator: Fear of displeasing God, fear for their health, fear of 'missing it' spiritually therefore following the OT law is known and can't be missing it because God Himself gave the law - so if they've missed it in the past in the crazy Charismatic world, at least they won't following the Mosaic law.
The word 'Judaizer' is found in Galatians 2:14 when Peter felt pressure from Jewish believers to eat with them, separating himself from Gentile believers. His action was hypocritical as Paul pointed out :
"You being a Jew live like the Gentiles and not like the Jews, so why are you now compelling the Gentiles to *live like the Jews?" (Greek literal: *live according to Jewish customs, or in English: Judaizer).
These Judaizers are the ones who pressured Paul and others to (selectively) observe all 3 parts of the laws of Moses. So if a believer pressures others to obey the worship/health laws of Moses, they aren't the modern term 'Messianic', but rather as scripture says, a Judaizer.
But for us "Christ is the end of the law for righteousness to all who believe" and "Love does no wrong to his neighbor, therefore love is the fulfillment of the law." (Galatians 3:25-26, Romans 7:7, 10:4, 13:8-10)
Now...what about Israel?
The common teaching is that spiritual Israel (believers in Jesus) have replaced natural Israel. It is built around natural Israel rejected their Messiah so God turned to the Gentiles, who have been grafted in (along with some believing Jews) and have become the 'real' Israel. Therefore to some, natural Israel means nothing.
This argument is blind to the larger purpose of the Lord, who says to Abraham in Genesis 12:3 of their covenant: "...and in you all the nations of the earth will be blessed", showing God's covenant with Abraham would include all nations, not just for his descendants that became the nation of Israel.
There would come a time when the Lord would stop referring to Jew and Gentile
By including 'all nations' it meant there would come a time when God would end making a distinction between Jew and Gentile because His larger purpose was for all nations to be in Him.
That time was Christ, which Paul understood: "...For you are all the children of God through faith in Christ Jesus...there is neither Jew nor Greek, neither slave nor free, neither male nor female; for you are all one in Christ Jesus. If you are in Christ you are a descendant of Abraham and heirs according to the promise." Galatians 3:26-29
The work of Jesus means in God's eyes only 2 types of people exist: Those who know Him and those who don't know Him. And those who do know Him have become a descendant of Abraham by that covenant.
Some believers who follow the law of Moses believe only spiritual Israel counts, again, not seeing the larger picture. Because the Father's larger plan was to include people of all nations, it is understood that Israel is included in 'all nations'.
We charismatic's take this verse out of context
We often use the verse 'The gifts and calling of God are without repentance' to give comfort to a friend who has perhaps missed God, and we encourage them that the Lord STILL has a plan and they haven't missed it beyond the point of no return.
But the context is actually about unbelieving Israel - the natural Israel. "From the standpoint of the gospel they are enemies for your sake, but from the standpoint of God's choice they are beloved for the sake of the fathers; for the gifts and calling of God are without repentance. For just as you once were disobedient to God, but now have been shown mercy, so these also now have been disobedient, that because of the mercy shown you they may now also be shown mercy. For God has shut up all of us in disobedience so that He may show mercy to all." Romans 11:28-32
Whatever way you've applied the gifts and calling of God are without repentance to yourself or a friend, it was actually written about unbelieving Israel, so apply it accordingly.
To this Paul continues: "I don't want you to be ignorant of this mystery brethren, so you won't be wise in your own self, that a partial hardening (blindness) has happened to Israel until the fullness of the Gentiles has come in; and so all Israel will be saved exactly as it is written: The deliverer will come from Zion, He will remove ungodliness from Jacob (Israel), This is my covenant with them, when I take away their sins."
So natural Israel matters both to world and to spiritual Israel.
If some reading this have specific questions I'm of course happy to answer specific questions, just email me at the email listed below. The fact is the Jewish and Gentile believers of the New Testament were overwhelmed by the new creation realities that Christ lived in them by virtue of the new birth.
Paul said in II Corinthians 5:16-17, "From this point on I know no person by natural standards (race, wealth, social class) for if a person is in Christ he is a new creature, old things have passed away and behold; All things have become new."
Paul measured people as God the Father now does, who no longer recognizes Jew nor Gentile, but only if they are His kids or not. What rule, what fast or feast, what formula could add to that miracle of being re-born into the Royal family of the Father God?
New subject next week, until then, blessings,