סימן כט סעיף יב

מִצְוָה עַל כָּל אָדָם, לֶאֱהֹב אֶת כָּל אֶחָד וְאֶחָד מִיִשְֹרָאֵל כְּגוּפוֹ, שֶׁנֶּאֱמַר וְאָהַבְתָּ לְרֵעֲךָ כָּמוֹךָ לְפִיכָךְ צָרִיךְ לְסַפֵּר בְּשִׁבְחוֹ (ועַיֵּן לקמן סִימָּן ל' סָעִיף ד), וְלָחוּס עַל מָמוֹנוֹ, כְּמוֹ שֶׁהוּא חָס עַל מָמוֹן שֶׁלּוֹ, וְרוֹצֶה בִּכְבוֹד עַצְמוֹ. וְהַמִּתְכַּבֵּד בִּקְלוֹן חֲבֵרוֹ, [אַף עַל פִּי שֶׁאֵין חֲבֵרוֹ עוֹמֵד שָׁם, וְלֹא הִגִּיעַ לוֹ בֹּשֶׁת, וְלֹא בִּיְשׁוֹ אֶלָּא עָרַךְ מַעֲשָׂיו הַטּוֹבִים וְחָכְמָתוֹ, לְמוּל מַעֲשֵׂה חֲבֵרוֹ, אוֹ חָכְמָתוֹ, כְּדֵי שֶׁיֵּרָאֶה מִכְּלָלוֹ, שֶׁהוּא מְכֻבָּד וַחֲבֵרוֹ בָּזוּי], אֵין לוֹ חֵלֶק לָעוֹלָם הַבָּא [עַד שֶׁיָּשׁוּב בִּתְשׁוּבָה שְׁלֵמָה] (רמב"ם הל' תשובה פ"ד ה"ד).

It is incumbent upon every Jew to love every fellow Jew as he loves himself, as it is said: "Love your neighbor as [you love] yourself."³⁸Leviticus 19:18. Therefore, you should relate [his] virtues³⁹You should not praise him to his adversaries as this would only prompt them to enumerate his faults. They would thus be violating the prohibition against lashon hara, telling malicious gossip. (Mishnah Berurah 156:4). and treat his property with [the same] concern as you have for your own property, or for your own honor. The person who glorifies himself in his neighbor's shame, even though his neighbor is not present and the humiliation has not reached him, and even if he has not actually insulted him, but only compared his own good deeds and his own wisdom with the good deeds or wisdom of his neighbor, so that from his statement he will be rated an honorable man and his neighbor as a despicable person, [this person] has no share in the World to Come unless he repents with perfect repentance.

תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)