The Rambam uses an unusual word in Hilchos Yesodei Hatorah 5:11: ולא ישתומם, which is translated on Sefaria as "and does not act so ridiculously".

I am not criticizing this translation, rather I am asking on what basis it was made, and are there alternative interpretations?

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> וְיֵשׁ דְּבָרִים אֲחֵרִים שֶׁהֵן בִּכְלַל חִלּוּל הַשֵּׁם. וְהוּא שֶׁיַּעֲשֶׂה אוֹתָם אָדָם גָּדוֹל בַּתּוֹרָה וּמְפֻרְסָם בַּחֲסִידוּת דְּבָרִים שֶׁהַבְּרִיּוֹת מְרַנְּנִים אַחֲרָיו בִּשְׁבִילָם. וְאַף עַל פִּי שֶׁאֵינָן עֲבֵרוֹת הֲרֵי זֶה חִלֵּל אֶת הַשֵּׁם כְּגוֹן שֶׁלָּקַח וְאֵינוֹ נוֹתֵן דְּמֵי הַמִּקָּח לְאַלְתַּר. וְהוּא שֶׁיֵּשׁ לוֹ וְנִמְצְאוּ הַמּוֹכְרִים תּוֹבְעִין וְהוּא מַקִּיפָן. אוֹ שֶׁיַּרְבֶּה בִּשְׂחוֹק אוֹ בַּאֲכִילָה וּשְׁתִיָּה אֵצֶל עַמֵּי הָאָרֶץ וּבֵינֵיהֶן. אוֹ שֶׁדִּבּוּרוֹ עִם הַבְּרִיּוֹת אֵינוֹ בְּנַחַת וְאֵינוֹ מְקַבְּלָן בְּסֵבֶר פָּנִים יָפוֹת אֶלָּא בַּעַל קְטָטָה וְכַעַס. וְכַיּוֹצֵא בַּדְּבָרִים הָאֵלּוּ הַכּל לְפִי גָּדְלוֹ שֶׁל חָכָם צָרִיךְ שֶׁיְּדַקְדֵּק עַל עַצְמוֹ וְיַעֲשֶׂה לִפְנִים מִשּׁוּרַת הַדִּין. וְכֵן אִם דִּקְדֵּק הֶחָכָם עַל עַצְמוֹ וְהָיָה דִּבּוּרוֹ בְּנַחַת עִם הַבְּרִיּוֹת וְדַעְתּוֹ מְעֹרֶבֶת עִמָּהֶם וּמְקַבְּלָם בְּסֵבֶר פָּנִים יָפוֹת וְנֶעֱלָב מֵהֶם וְאֵינוֹ עוֹלְבָם. מְכַבֵּד לָהֶן וַאֲפִלּוּ לַמְקִלִּין לוֹ. וְנוֹשֵׂא וְנוֹתֵן בֶּאֱמוּנָה. וְלֹא יַרְבֶּה בַּאֲרִיחוּת עַמֵּי הָאָרֶץ וִישִׁיבָתָן. וְלֹא יֵרָאֶה תָּמִיד אֶלָּא עוֹסֵק בַּתּוֹרָה עָטוּף בְּצִיצִית מֻכְתָּר בִּתְפִלִּין וְעוֹשֶׂה בְּכָל מַעֲשָׂיו לִפְנִים מִשּׁוּרַת הַדִּין. וְהוּא שֶׁלֹּא יִתְרַחֵק הַרְבֵּה **וְלֹא יִשְׁתּוֹמֵם**. עַד שֶׁיִּמָּצְאוּ הַכּל מְקַלְּסִין אוֹתוֹ וְאוֹהֲבִים אוֹתוֹ וּמִתְאַוִּים לְמַעֲשָׂיו. הֲרֵי זֶה קִדֵּשׁ אֶת ה' וְעָלָיו הַכָּתוּב אוֹמֵר (ישעיה מט ג) "וַיֹּאמֶר לִי עַבְדִּי אָתָּה יִשְׂרָאֵל אֲשֶׁר בְּךָ אֶתְפָּאָר":
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> There are other things included in blasphemy, although they are not of themselves either among the mandatory or prohibitive commandments, as for example, when a great man, famed for his learning and piety, will do something that the public will suspect him on account thereof, even though such deeds be not transgressions, yet he has committed blasphemy, as for example: if he makes a purchase and does not pay for it at once,10 although he has the money and the vendors are claiming it and he delays them; or if he indulges in frivolity, or doth eat and drink with and among the ignorant,11 or if his speech with his fellow men be not polite, or if he does not receive them pleasantly, but acts as one looking for strife and shows anger. In such and like matters, all measured by the standard of the greatness of such scholar, he must take particular care, and act exceedingly better than the law requires. Conversely, if the scholar restrains himself, speaks politely to his fellow men, and when among them acts like one of them, and receives them pleasantly, takes abuse from them but never gives abuse to them in return, respects them, even those who do not respect him, acts in business honestly, does not remain in company with the unlearned, nor visits their assemblies, and is rarely seen otherwise than to be engaged in the study of the Torah, wrapt in the prayer-garment and adorned with phylacteries, and performs his duties exceedingly more than the law requires, provided he does not go to extremes **and does not act so ridiculously,** so that all praise him and love him and crave to imitate his actions, behold he doth sanctify the Lord, and concerning him, the verse speaks, saying: "And He said unto me, thou art my servant, Israel, in whom I am glorified." (Is. 49.3).
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