Bamidbar Rabbah, a collection of Midrashic teachings on the Book of Numbers, tackles this very question, and the answer might surprise you.

The passage begins with a seemingly straightforward verse from Numbers 5:6: “Speak to the children of Israel: A man or woman, when they will perform any sin of a person, to commit a trespass against the Lord, and that individual shall be guilty.” But as is so often the case, the Rabbis see much more beneath the surface.

Rabbi Abbahu, in a beautiful interpretation, connects this verse to Hosea 14:8, "Those who dwell in His shadow will return." He says this refers to proselytes – converts – who "come and take refuge in the shadow of the Holy One, blessed be He." They are not just accepted, but cherished.

But the connection goes even deeper. The verse in Hosea continues, "They will give life to grain." The Midrash interprets "grain" as an allusion to the Talmud. Just as grain nourishes the body, the Talmud nourishes the soul (Etz Yosef, Maharzu). And "will blossom like the vine" refers to Aggadah—the storytelling and wisdom traditions—which are considered sweet like wine. This suggests that converts are not just recipients of Jewish wisdom, but active participants in its growth and flourishing!

The text continues, "Their repute is like the wine of Lebanon." The Holy One, blessed be He, says that the names of proselytes are as dear as the wine poured as a libation on the altar. But why Lebanon? Because, the Midrash explains, Lebanon "whitens [malbin] the sins of Israel like snow," echoing Isaiah 1:18: "If your sins will be like scarlet, they will be whitened as snow." Converts, in a sense, help to purify and elevate the entire community.

Rabbi Shimon ben Yoḥai adds that Lebanon is associated with joy: "all the hearts [halevavot] are joyous in it," as in Psalms 48:3, "Beautiful in its view, joy of all the world." The Rabbis offer another reason, linking it to I Kings 9:3: "My eyes and My heart [velibi] will be there always." Lebanon, and by extension, converts, are close to God's heart.

The Midrash then draws a parallel between the treatment of native-born Israelites and converts. Just as the Torah outlines restitution for wrongs committed against an Israelite in Leviticus 5:21, so too does it emphasize the importance of fair treatment of converts. If someone robs a convert, it's as if they robbed an Israelite. The same language of sin, trespass, guilt, and restitution applies to both. The passage emphasizes that the same rules and protections apply equally to both groups.

We find that the same consequences of sin apply in both cases: "A person who shall sin… commit a trespass against the Lord… and that individual shall be guilty," and so on. The message is clear: converts are not second-class citizens. They are fully integrated into the covenant.

Ultimately, Bamidbar Rabbah teaches us that converts are not merely welcomed into the Jewish community, but are considered vital and cherished members. They are likened to grain and vines, essential for nourishment and growth. They help to purify and bring joy to the community. They are, in essence, just as important as those born into the tradition. It’s a powerful reminder that Judaism isn't about bloodlines, but about embracing a way of life and being welcomed with open arms.