Should Christians Convert To Judaism...even if they don't deny Christ?

So a question came up today; as it has for the past two weeks for some odd reason. The question is "Can Christians follow Torah, and the New Testament and deny Christianity?" Then when you start talking to these people the question quickly turns to "Can a Gentile Christian become a Messianic Jew (A Jew who accepts Jesus as Messiah)? From there the question, comes up "What holidays do you follow and why?"y

So I am going to write tonight about "Should Christians convert to Messianic Judaism?" And my short answer is "NO!" Why? There is no precedent for such a conversion within the Bible. Matter of fact, Paul himself, taught against Judaizing Gentiles. A Judaizer taught that, in order for a Christian to truly be right with God, he must conform to the Mosaic Law. Circumcision, especially, was promoted as necessary for salvation. Gentiles had to become Jewish proselytes first, and then they could come to Christ. The doctrine of the Judaizers was a mixture of grace (through Christ) and works (through the keeping of the Law). This false doctrine was dealt with in Acts 15 and strongly condemned in the book of Galatians.

Let's look at Acts 15; in Acts 15, we see that Paul and Barnabas were meeting with the Jerusalem council. There were those who were teaching "Unless you are circumcised according t the custom of Moses you can't be saved." Paul and Barnabas both argued with these people and later we see in verses 8-10 "8 And God, who knows the heart, bore witness to them, by giving them the Holy Spirit just as he did to us, 9 and he made no distinction between us and them, having cleansed their hearts by faith. 10 Now, therefore, why are you putting God to the test by placing a yoke on the neck of the disciples that neither our fathers nor we have been able to bear?" You see their own father's couldn't work their way into Heaven. 

First Timothy 4:3 says that, in later times, false teachers will “forbid people to marry and order them to abstain from certain foods, which God created to be received with thanksgiving by those who believe and who know the truth.” The Judaizers upheld the Mosaic Law as necessary for salvation; viewing Christ’s death as being insufficient without the active and continued cooperation of the one being saved.

The Bible is clear that the attempt to add human works to God’s grace overlooks the very meaning of grace, which is “undeserved blessing.” As Paul says, “If by grace, then it cannot be based on works; if it were, grace would no longer be grace” (Romans 11:6). Praise the Lord, “Christ has set us free. Stand firm, then, and do not let yourselves be burdened again by a yoke of slavery” (Galatians 5:1). 

So now, should a Gentile believer convert?  No. Even Ruth was recognized as a Moabite through out the book. As far as the "Ger' or the foreigner living among Israel; even when they were circumcised they were regarded as a Ger Tzedek (Righteous Alien).

Exodus 12:48 states 48 If a stranger shall sojourn with you and would keep the Passover to the LORD, let all his males be circumcised. Then he may come near and keep it; he shall be as a native of the land. But no uncircumcised person shall eat of it. 

Although the passage shows that Gentiles could choose to observe Jewish life they were still called Gerim (outsiders). There is nothing that can be added; because as Paul wrote in Galatians 2:21 states "21 I do not nullify the grace of God, for if righteousness were through the law, then Christ died for no purpose."