A major theme of פרשת קדושים are its numerous ethical laws. The one law that is often overlooked is the commandment ואהבתם את הגר, that we must love the convert.
In the Parsha, it’s worded as ואהבת לו כמוך, that you should love him like yourself. The question that is asked is why is there a separate Mitzva to love the convert when we are not supposed to remind someone that he’s a convert. This is a separate prohibition of לא תונו, not to oppress.
The answer that is given is that we need to make a special effort to understand the convert. Every one of them has his own story. It is unusual to find two converts who have a similar story.
With Jews, we only need to ask what country he comes from and we are able to know his origins. This is true among Ashkenazi and Sephardi Jews, or even Chassidic Jews.
This is why we have a Mitzva of loving the convert. We need to love him and understand him. Shabbat Shalom