According to Jewish law, it is, in the case of a Jewish father and a non-Jewish mother, the child is not a Jew.
Being born into it is the most common and ‘supported’ way.
Judaism is actually one of the major world religions, though it's much smaller in terms of population compared to Christianity, Islam, or Hinduism [1]. Despite its smaller numbers, it has had a significant influence on Western culture, ethics, and religious thought, particularly as the foundation for both Christianity and Islam.
Christianity requires (depending on who you ask/sect) - believing in Christ as your savior, or baptism, or being confirmed. Generally not an arduous process.
Hinduism, you believe in the Dharma, and as long as you aren’t angering people enough they kick you out, you are Hindu. Some would argue, as long as you don’t believe you are something else, you are Hindu. Notably, caste can be tricky. There might also be a form you should fill out.[https://hinduism.stackexchange.com/questions/407/is-it-true-...]
Buddhism, you join the Sangha (show up), or follow teachings. There is no test or anything. Many Buddhists don’t directly do those things, and I’ve never heard anything say they ‘weren’t Buddhist’. Maybe a terrible Buddhist, but what else is new?
By those standards, is not Judaism the toughest and most difficult? Personally, I’d take it as a point of pride.
> Generally not an arduous process.
Why not ask Jesus? He said it requires giving everything you have to the kingdom, following the spirit of the Law more fully than the Jews themselves do, and loving the Lord and your neighbor with all your heart. He additionally said that many who claim to be Christian are not, and will be judged accordingly.