תָּנוּ רַבָּנַן גֵּר שֶׁבָּא לְהִתְגַּיֵּיר בִּזְמַן הַזֶּה אוֹמְרִים לוֹ מָה רָאִיתָ שֶׁבָּאתָ לְהִתְגַּיֵּיר אִי אַתָּה יוֹדֵעַ שֶׁיִּשְׂרָאֵל בִּזְמַן הַזֶּה דְּווּיִים דְּחוּפִים סְחוּפִים וּמְטוֹרָפִין וְיִסּוּרִין בָּאִין עֲלֵיהֶם אִם אוֹמֵר יוֹדֵעַ אֲנִי וְאֵינִי כְּדַאי מְקַבְּלִין אוֹתוֹ מִיָּד
וּמוֹדִיעִין אוֹתוֹ מִקְצָת מִצְוֹת קַלּוֹת וּמִקְצָת מִצְוֹת חֲמוּרוֹת וּמוֹדִיעִין אוֹתוֹ עֲוֹן לֶקֶט שִׁכְחָה וּפֵאָה וּמַעְשַׂר עָנִי
וּמוֹדִיעִין אוֹתוֹ עׇנְשָׁן שֶׁל מִצְוֹת אוֹמְרִים לוֹ הֱוֵי יוֹדֵעַ שֶׁעַד שֶׁלֹּא בָּאתָ לְמִדָּה זוֹ אָכַלְתָּ חֵלֶב אִי אַתָּה עָנוּשׁ כָּרֵת חִלַּלְתָּ שַׁבָּת אִי אַתָּה עָנוּשׁ סְקִילָה וְעַכְשָׁיו אָכַלְתָּ חֵלֶב עָנוּשׁ כָּרֵת חִלַּלְתָּ שַׁבָּת עָנוּשׁ סְקִילָה
וּכְשֵׁם שֶׁמּוֹדִיעִין אוֹתוֹ עׇנְשָׁן שֶׁל מִצְוֹת כָּךְ מוֹדִיעִין אוֹתוֹ מַתַּן שְׂכָרָן אוֹמְרִים לוֹ הֱוֵי יוֹדֵעַ שֶׁהָעוֹלָם הַבָּא אֵינוֹ עָשׂוּי אֶלָּא לְצַדִּיקִים וְיִשְׂרָאֵל בִּזְמַן הַזֶּה אֵינָם יְכוֹלִים לְקַבֵּל
The Sages taught: With regard to a potential convert who comes to a court in order to convert, at the present time, when the Jews are in exile, the judges of the court say: What did you see that motivated you to come to convert? Don’t you know that the Jewish people at the present time are anguished, suppressed, despised, and harassed, and hardships are frequently visited upon them? If the potential conver says: I know, and although I am unworthy of joining the Jewish people and sharing in their sorrow, I nevertheless desire to do so, then the court accepts the convert immediately to begin the conversion process.
And the judges of the court inform the convert of some of the lenient mitzvot and some of the stringent mitzvot, and they inform the convert of the sin of neglecting the mitzva to allow the poor to take gleanings, forgotten sheaves, and produce in the corner of one’s field, and about the poor's tithe.
They inform the convert of the punishment for transgressing the mitzvot, as follows: They say: Be aware that before you came to this status and converted, had you eaten forbidden fat, you would not be punished in the afterlife (karet), and had you profaned Shabbat, you would not be punished by stoning, since these prohibitions do not apply to gentiles. But now, once converted, if you have eaten forbidden fat you are punished in the afterlife (karet), and if you have profaned Shabbat, you are punished by stoning.
And just as they inform the convert about the punishment for transgressing the mitzvot, so too, they inform the convert about the reward granted for fulfilling them. They say: Be aware that the World-to-Come is made only for the righteous, and if you observe the mitzvot you will merit it, and be aware that the Jewish people, at the present time, are unable to receive their full reward in this world;
לֹא רוֹב טוֹבָה וְלֹא רוֹב פּוּרְעָנוּת וְאֵין מַרְבִּין עָלָיו וְאֵין מְדַקְדְּקִין עָלָיו
קִיבֵּל מָלִין אוֹתוֹ מִיָּד נִשְׁתַּיְּירוּ בּוֹ צִיצִין הַמְעַכְּבִין אֶת הַמִּילָה חוֹזְרִים וּמָלִין אוֹתוֹ שְׁנִיָּה נִתְרַפֵּא מַטְבִּילִין אוֹתוֹ מִיָּד וּשְׁנֵי תַּלְמִידֵי חֲכָמִים עוֹמְדִים עַל גַּבָּיו וּמוֹדִיעִין אוֹתוֹ מִקְצָת מִצְוֹת קַלּוֹת וּמִקְצָת מִצְוֹת חֲמוּרוֹת טָבַל וְעָלָה הֲרֵי הוּא כְּיִשְׂרָאֵל לְכׇל דְּבָרָיו
אִשָּׁה נָשִׁים מוֹשִׁיבוֹת אוֹתָהּ בְּמַיִם עַד צַוָּארָהּ וּשְׁנֵי תַּלְמִידֵי חֲכָמִים עוֹמְדִים לָהּ מִבַּחוּץ וּמוֹדִיעִין אוֹתָהּ מִקְצָת מִצְוֹת קַלּוֹת וּמִקְצָת מִצְוֹת חֲמוּרוֹת
אָמַר מָר גֵּר שֶׁבָּא לְהִתְגַּיֵּיר אוֹמְרִים לוֹ מָה רָאִיתָ שֶׁבָּאתָ לְהִתְגַּיֵּיר וּמוֹדִיעִים אוֹתוֹ מִקְצָת מִצְוֹת קַלּוֹת וּמִקְצָת מִצְוֹת חֲמוּרוֹת מַאי טַעְמָא דְּאִי פָּרֵישׁ נִפְרוֹשׁ דְּאָמַר רַבִּי חֶלְבּוֹ קָשִׁים גֵּרִים לְיִשְׂרָאֵל כְּסַפַּחַת דִּכְתִיב וְנִלְוָה הַגֵּר עֲלֵיהֶם וְנִסְפְּחוּ עַל בֵּית יַעֲקֹב
they are not able to receive either an abundance of good nor an abundance of calamities, since the primary place for reward and punishment is in the World-to-Come. And they do not overwhelm the convert with threats, and they are not exacting about the details of the mitzvot.
If the male convert accepts all of these ramifications, then they circumcise him immediately. If there still remain on him shreds of flesh from the foreskin that invalidate the circumcision, they circumcise him again a second time to remove them. When he is healed from the circumcision, they immerse him immediately, and two Torah scholars stand over him at the time of his immersion and inform him of some of the lenient mitzvot and some of the stringent mitzvot. Once he has immersed and emerged, he is like a born Jew in every sense.
For the immersion of a female convert: Women appointed by the court seat her in the water of the ritual bath up to her neck, and two Torah scholars stand outside the bath house so as not to compromise her modesty, and from there they inform her of some of the lenient mitzvot and some of the stringent mitzvot.
...
The Gemara analyzes the original teaching from the top (baraita). The Master said in the baraita: With regard to a potential convert who comes to a court in order to convert, the judges of the court says to the convert: What did you see that motivated you to come to convert? And they inform the convert of some of the lenient mitzvot and some of the stringent mitzvot.
The Gemara asks: What is the reason to say this to him? It is so that if he is going to withdraw from the conversion process, let him withdraw already at this stage.
He should not be convinced to continue, as Rabbi Ḥelbo said: Converts are as harmful to the Jewish people as a leprous scab [sappaḥat] on the skin, as it is written: “And the convert shall join himself with them, and they shall cleave [venispeḥu] to the house of Jacob” (Isaiah 14:1). This alludes to the fact that the cleaving of the convert to the Jewish people is like a scab.
אמר ריש לקיש חביב הוא הגר שנתגייר, מישראל בעמידתן על הר סיני, למה לפי שאילולי שראו קולות וברקים וההרים רועשים וקול שופרות, לא היו מקבלים את התורה, וזה שלא ראה אחד מהם, בא והשלים עצמו להקב"ה, וקיבל עליו מלכות שמים, יש לך חביב מזה.
Resh Laqish said: The proselyte who converts is more beloved than Israel when they stood at Mount Sinai. Why? Because, if they had not seen the thunder and lightning, the mountains trembling, and the noise of the trumpets, they would not have accepted the Torah. But this < proselyte >, who did not see one of them, came to the Holy One, and took upon themself the Yoke of Heaven. Is there one of you more lovable than this one?