Because of centuries of secrecy make it difficult to prove that an individual secret jew has kept all the requisite halakhist laws or that blood and heritage jewishness was maintained and kept unbroken all that way back, a Crypto-Jew must go through an official conversion process, just to make sure.
Even if his family oral history indicates his claims are true, if the or she is really serious about declaring himself a Jew and living a Jewish life, he should not object to doing this.
To prove this point :
Imagine that someone writes to our Canadian immigration and says ” Although I am a citizen of a foreign country, I have always been Canadian, secretly, in my heart , and so has my family. I want to be accepted as a Canadian citizen”.
Immigration Canada, would say to him: ” If you want to be a Canadian citizen, you have to follow certain protocol”.
You have to come here, take classes and learn our laws, pass a test, and be naturalized , and then we will give you all the benefits of citizenship. You will get a Canadian passport and you will be allowed to vote.
Not matter what you claim in your heart, not until then will we consider you a Canadian citizen entitled to all the rights , privileges and protection under our laws.
Read our post on ‘Alternative to Conversion and “Ceremony of Return ”