כִּ֣י חֶשְׁבּ֔וֹן עִ֗יר סִיחֹ֛ן מֶ֥לֶךְ הָאֱמֹרִ֖י הִ֑וא וְה֣וּא נִלְחַ֗ם בְּמֶ֤לֶךְ מוֹאָב֙ הָֽרִאשׁ֔וֹן וַיִּקַּ֧ח אֶת־כׇּל־אַרְצ֛וֹ מִיָּד֖וֹ עַד־אַרְנֹֽן׃
For Ḥeshbon was the city of Siĥon the king of the Emori, who had fought against the former king of Mo᾽av, and taken all his land out of his hand, as far as Arnon.
עַל־כֵּ֛ן יֹאמְר֥וּ הַמֹּשְׁלִ֖ים בֹּ֣אוּ חֶשְׁבּ֑וֹן תִּבָּנֶ֥ה וְתִכּוֹנֵ֖ן עִ֥יר סִיחֽוֹן׃
Wherefore they who speak in similes say, Come to Ḥeshbon, let the city of Siĥon be built and established:
אָמַר רַבִּי שְׁמוּאֵל בַּר נַחְמָן אָמַר רַבִּי יוֹחָנָן מַאי דִּכְתִיב עַל כֵּן יֹאמְרוּ הַמֹּשְׁלִים וְגוֹ׳
The Gemara cites a related discussion. Rabbi Shmuel bar Naḥman says that Rabbi Yoḥanan says: What is the meaning of that which is written: “Therefore they that speak in parables [hamoshlim] say: Come to Heshbon! Let the city [ir] of Sihon be built and established! For a fire is gone out of Heshbon, a flame from the city of Sihon; it has devoured Ar of Moab, the lords of the high places of Arnon” (Numbers 21:27–28)?
הַמֹּשְׁלִים אֵלּוּ הַמּוֹשְׁלִים בְּיִצְרָם בּוֹאוּ חֶשְׁבּוֹן בּוֹאוּ וּנְחַשֵּׁב חֶשְׁבּוֹנוֹ שֶׁל עוֹלָם הֶפְסֵד מִצְוָה כְּנֶגֶד שְׂכָרָהּ וּשְׂכַר עֲבֵירָה כְּנֶגֶד הֶפְסֵדָהּ
The Gemara interprets these verses homiletically. “Hamoshlim”; these are the people who rule over [hamoshlim] their evil inclination. They will say: “Come to Heshbon,” meaning: Come and let us calculate the account of [ḥeshbono] the world, i.e., the financial loss incurred by the fulfillment of a mitzva in contrast to its reward, and the reward for committing a transgression, i.e., the pleasure and gain received, in contrast to the loss it entails.