The Jewish religion is not evangelistic, but many people in the ancient world were attracted to certain features of it: belief in one righteous God, high moral standards, emphasis on close family ties.
In the New Testament period many people, including some Roman officials, became followers of the Jews’ religion, and these were known as proselytes.
Technically, Gentile proselytes could never actually be Jews (since being a Jew requires being born a Jew), but some proselyte men went so far as to have themselves circumcised.
Some Gentiles who were drawn to the Jews’ religion were known as “God-fearers.” These included the devout Roman centurion Jesus encountered, and another centurion, Cornelius, who became a Christian after meeting the apostle Peter (Acts 10–11).
There was no clear distinction between God-fearers and proselytes; both terms applied to Gentiles who in some way followed the faith of the Jews.
Because proselytes chose the Jewish religion, they were sometimes more devout than the Jews themselves.
Some Bible translations use “converts to Judaism” or “devout converts” instead of “proselytes.”