Our parasha includes one of the mentions of the commandment to be kind to gerim (converts). "As a citizen of yours he shall be for you, the convert who lives with you, and you shall love him as yourself for you were strangers in the Land of Egypt" (Vayikra 19:34). Since the convert is a full Jew, why must the Torah tell us separately to love him? Chazal understand that there is a need to strengthen this general directive in relation to converts. But why? The Ibn Ezra (ad loc.) says it is because a convert generally has a weaker social status. The Sefer Hachinuch (#431) similarly focuses on the difficulty of leaving his natural surroundings to join a foreign nation. The Rambam (Aseh 207) highlights the extra respect he deserves for going out of his way to accept Hashem’s Torah, comparing love of a ger to love of Hashem Himself (see also De’ot 6:4).
The differing approaches may depend on how one views the connections between our pasuk’s parts. After commanding to love the ger, the Torah apparently provides a reason: "for you were strangers..." In other words, we should be sensitive to difficult situations similar to the one we experienced. This fits well with the Ibn Ezra and Chinuch.
The Rambam may focus on the earlier part of the pasuk. Torat Kohanim (ad loc.) learns from the words, "as a citizen of yours he shall be," not to treat him as other Jews, but as a directive to accept a ger only if he accepts all of a Jew’s obligations. If the pasuk stresses the serious religious commitment required, we understand the connection to the commandment to love him. After all, one who embraces Hashem in a dedicated manner deserves it more than the average Jew, who is simply born into Judaism.
This understanding of the Rambam explains an apparent contradiction. The Rambam (Issurei Bi’ah 13: 15,17) talks about gerim who were accepted when it is unclear whether their motivation was noble or self-serving. In one place he says that we wait to see how they turn out before deciding whether to push them away or embrace them. In another place he says that even if their secret is uncovered, we consider them to be valid converts. While some Acharonim view the statements as referring to the conversion’s status, our mentor, Rav Yisraeli (Chavot Binyamin 67) explains that the conversion even with questionable intentions is valid. The issue is whether we should embrace and love the convert as the Torah usually requires, or whether we should give him a cold shoulder due to his insincere motives. Since the Rambam views the reason to love converts as their willingness to embrace Hashem, not their difficult situation, it makes full sense that when a conversion was self-serving, the ger does not deserve our affection.
The existence of converts with questionable motives has caused some to generally look askance on gerim. However, we should be careful not to throw out the baby with the bath water.