a change of religion; "his conversion to the Catholic faith"

The ritual of a Gentile becoming a proselye to Rabbinic Judaism, Gentile Conversion is not necessary in Messianic Judaism.

self-conscious commitment to a religious faith and practice sometimes accompanied by behavioral "signs"

Halacha tells us that only a person born of a Jewish mother is Jewish. Those who choose to take on the Jewish religion must undertake study to be sure that this is what they really want and also to become knowledgeable Jews able to practice the rituals and observe Mitzvot (commandments). The ceremony of conversion requires evidence of knowledge, circumcision (for men), and mikveh (ritual immersion in running water). AVEN, Davenen; (Yiddish):Pray, praying.

Turning from one religion (or no religion) to a particular religion.