Please tell me the steps ancient Jews went through to become a rabbi? Has this changed, or it still the same?
In ancient times, the concept of a rabbi was understood as somebody with semicha, meaning somebody who has been given rabbinic authority from an ‘authoritzed’ rabbi, under the assumption that the chain of authorization goes back to the time of receiving the Torah. The status of samuch (one who has received semicha) gave the rabbi special powers of durisdiction.
After the chain was broken, and the institution of semicha lost, rabbinic authority became a question of recognition as an erudite scholar with the capability of deciding difficult and new halachic questions. Yet, now as then, a person is only considered a rabbi if he has received rabbinic ordination from a rabbi, who tests him and knows that he is worthy of the title. This rabbinic ordination is known as semicha, even though it is not equivalent with the original meaning of the term.
In the State of Israel, the concept has been institutionalized in the form of the Rabbinate. This ensures a fixed standard of rabbis, yet loses the personal contact between the rabbi giving the semicha and the newly appointed rabbi.