"And these are the garments that they shall make" (Exodus 28:4). Our Rabbis taught: A person should always be humble like Hillel and not impatient like Shammai, and so forth. There was another incident concerning a certain gentile who was passing behind a synagogue and heard a scribe reading aloud, "And these are the garments that they shall make." He came to the scribe and said to him, "Explain these to me." He explained them to him. He said to him, "For whom are these?" He said to him, "For the High Priest." That gentile said to himself, "I will go and convert so that they will appoint me High Priest." He came before Shammai and said, "Convert me on the condition that you appoint me High Priest." Shammai pushed him away with the builder's measuring rod that was in his hand. He came before Hillel, who converted him. Hillel said to him, "Does one appoint before the king anyone but one who knows the protocols of royalty? Go and learn the protocols of the kingship." He went and read, and when he reached "and the stranger who draws near shall be put to death" (Numbers 1:51), he asked, "About whom is this verse said?" They told him, "Even about David king of Israel." That convert reasoned a fortiori about himself. He said, "If Israel, who are called children of the Omnipresent, and because He loved them He called them, 'Israel is My firstborn son' (Exodus 4:22), yet of them it is written, 'and the stranger who draws near shall be put to death,' then how much more so a mere convert who comes with his staff and his bag," and so forth.
The Convert Who Wished to Be High Priest and Hillel's Patience
Yalkut Shimoni on Torah 379:2
(שמות כח ד) וְאֵלֶּה הַבְּגָדִים אֲשֶׁר יַעֲשׂוּ וְגוֹ'. תָּנוּ רַבָּנָן. לְעוֹלָם יְהֵא אָדָם עַנְוְתָן כְּהִלֵל וְכוּ'. עוֹד מַעֲשֶׂה בְּגוֹי אֶחָד שֶׁהָיָה עוֹבֵר אֲחוֹרֵי בֵּית הַכְּנֶסֶת וְשָׁמַע סוֹפֵר שְׁמְּקָרֵא וְאֵלֶּה הַבְּגָדִים אֲשֶׁר יַעֲשׂוּ וְגוֹ'. בָּא אֵצֶל הַסּוֹפֵר. אֲמַר לֵיהּ, פָּרְשֵׁהוּ לִי. פֵּרֵשׁ לוֹ. אֲמַר לֵיהּ, הַלָּלוּ לְמִי. אֲמַר לֵיהּ, לְכֹהֵן גָּדוֹל. אָמַר אוֹתוֹ גּוֹי בְּעַצְמוֹ, אֵלֵךְ וְאֶתְגַּיֵּר עַל מְנַת שֶׁתְּשִׂימֵנִי כֹּהֵן גָּדוֹל. בָּא אֵצֶל שַׁמַּאי. דְּחָפוֹ בְּאַמַּת הַבִּנְיָן שֶׁבְּיָדוֹ. בָּא לִפְנֵי הִלֵּל, אָמַר, גַּיְּרֵנִי עַל מְנַת שֶׁתְּשִׂימֵנִי כֹּהֵן גָּדוֹל. גִּיְּרָהוּ. אֲמַר לֵיהּ, כְּלוּם מַעֲמִידִין לִפְנֵי הַמֶּלֶךְ אֶלָּא מִי שֶׁיּוֹדֵעַ טַכְסִיסֵי מַלְכוּת, לֵךְ לְמֹד טַכְסִיסֵי מַלְכוּת. הָלַךְ וְקָרָא, כֵּיוַן שֶׁהִגִּיעַ לְ"וְהַזָּר הַקָּרֵב יוּמָת" אָמַר, מִקְרָא זֶה עַל מִי נֶאֱמַר. אָמְרוּ לוֹ, אֲפִלּוּ עַל דָּוִד מֶלֶךְ יִשְׂרָאֵל. נָשָׂא אוֹתוֹ גֵּר קַל וָחֹמֶר בְּעַצְמוֹ. אָמַר, וּמַה יִּשְׂרָאֵל שֶׁנִּקְרְאוּ בָּנִים לַמָּקוֹם, מִתּוֹךְ שֶׁאֲהֵבָן קְרָאָן "בְּנִי בְכֹרִי יִשְׂרָאֵל", כְּתִיב בְּהוּ "וְהַזָּר הַקָּרֵב יוּמָת", גֵּר הַקַּל הַבָּא בְּמַקְלוֹ וּבְתַרְמִילוֹ עַל אַחַת כַּמָּה וְכַמָּה וְכוּ'.