The Torah teaches us that Abraham and Sarah actively encouraged the people they met in Haran to join their small community in worshiping the one imageless God. “Abram took his wife Sarai, his nephew Lot, all their accumulated property, and the souls they had made in Haran, and they left to go to the land of Canaan.” Genesis 12:5
Since it is impossible to make a soul, this verse must refer to the people that Abram and Sarai influenced to join them in their religious quest. (Midrash Genesis Rabbah 39:14)
The Zohar says that all these converts formed a large caravan whose merits protected Abram and Sarai as they traveled from city to city.
Ever since that time the merits of converts to Judaism have added to the strength of the Jewish people and thus helped protect us on our long journey.
If this is true why do many Jews fail to encourage non-Jews to become Jewish? Sometimes they fear a negative reaction on the part of the non-Jew or on the part of the larger non-Jewish society.
The Midrash correctly indicates that Abraham and Sarah both influenced non-Jews to become Jewish but it doesn’t explain why Sarai made more converts than Abraham. He should have influenced more non-Jews to become Jewish than Sarah since he traveled around more and had greater opportunities to meet people.
Unfortunately, Abraham sometimes rebuffed non-Jews. Rabbi Yohanan claimed that Abraham “barred people from entering under the wings of the Shekinah” (converting to Judaism) and that is why his descendants were enslaved in Egypt. (Talmud Nedarim 32a)
Rabbi Yohanan specifically criticized Abraham for discouraging Timna the sister of Lotan (Genesis 36:12) who the Rabbis determined wanted to convert to Judaism.
Because Timna was rebuffed by Abraham, she married a pagan. Her son Amalek passed on her resentment to his descendants who became the tribe that attacked the Jewish people when they were on the way to Mount Sinai. (Talmud Sanhedrin 99b)
Thus our sages taught that a negative attitude toward non-Jews who are interested in becoming Jewish can lead to anti-Semitism in later generations.
How do we know that Sarah was more successful in encouraging non-Jews to convert to Judaism? Years later when God tells Abraham, “Abide by everything that Sarah tells you” (Genesis 21:12) the Midrash explains, “You should listen to Sarah since in prophecy she is on a higher level than you.”
How could Sarah be on a higher spiritual level than Abraham? Because she influenced more non-Jews to become Jewish than Abraham did.
This is why the Zohar claims Genesis 12:15 “He was good to Abram because of her” means that God (not Pharaoh) was good to Abram because of Sarai. Why? Because Sarai had influenced so many non-Jews to become Jewish.
So when Jewish women influence non-Jews to become Jewish even their husbands benefit from the process.
Sarah’s enthusiastic encouragement of non-Jews to become Jewish set a good example for her daughters and granddaughters. Indeed, her great granddaughter Dinah influenced one of the most righteous men in all of history to convert to Judaism when she married him. His name was Job. (Midrash Genesis Rabbah 76)
Even today, I know of several grandmothers who influenced the non-Jews their grandchildren married to become Jewish. One of them is a rabbi today.