We learned in the mishna: They said about Rabbi Ḥanina ben Dosa that the indication whether or not his prayer was accepted was whether the prayer was fluent in his mouth as he recited it. The Gemara asks: From where are these matters, that this is an accurate indication of whether or not his prayer was accepted, derived? Rabbi Yehoshua ben Levi said: As the verse stated: “Adonai who creates the expression of the lips says, Peace, peace, to him that is far off and to him that is near; and I will heal him” (Isaiah 57:19). It can be inferred from this verse that if speech of the lips, fluent speech, is granted to one who prays, it indicates that his prayer on behalf of the ill has been accepted and I will heal him, that person will be healed.
(יד) וְאָמַ֥ר סֹֽלּוּ־סֹ֖לּוּ פַּנּוּ־דָ֑רֶךְ הָרִ֥ימוּ מִכְשׁ֖וֹל מִדֶּ֥רֶךְ עַמִּֽי׃ (ס) (טו) כִּי֩ כֹ֨ה אָמַ֜ר רָ֣ם וְנִשָּׂ֗א שֹׁכֵ֥ן עַד֙ וְקָד֣וֹשׁ שְׁמ֔וֹ מָר֥וֹם וְקָד֖וֹשׁ אֶשְׁכּ֑וֹן וְאֶת־דַּכָּא֙ וּשְׁפַל־ר֔וּחַ לְהַחֲיוֹת֙ ר֣וּחַ שְׁפָלִ֔ים וּֽלְהַחֲי֖וֹת לֵ֥ב נִדְכָּאִֽים׃ (טז) כִּ֣י לֹ֤א לְעוֹלָם֙ אָרִ֔יב וְלֹ֥א לָנֶ֖צַח אֶקְּצ֑וֹף כִּי־ר֙וּחַ֙ מִלְּפָנַ֣י יַֽעֲט֔וֹף וּנְשָׁמ֖וֹת אֲנִ֥י עָשִֽׂיתִי׃ (יז) בַּעֲוֺ֥ן בִּצְע֛וֹ קָצַ֥פְתִּי וְאַכֵּ֖הוּ הַסְתֵּ֣ר וְאֶקְצֹ֑ף וַיֵּ֥לֶךְ שׁוֹבָ֖ב בְּדֶ֥רֶךְ לִבּֽוֹ׃ (יח) דְּרָכָ֥יו רָאִ֖יתִי וְאֶרְפָּאֵ֑הוּ וְאַנְחֵ֕הוּ וַאֲשַׁלֵּ֧ם נִֽחֻמִ֛ים ל֖וֹ וְלַאֲבֵלָֽיו׃ (יט) בּוֹרֵ֖א נוב [נִ֣יב] שְׂפָתָ֑יִם שָׁל֨וֹם ׀ שָׁל֜וֹם לָרָח֧וֹק וְלַקָּר֛וֹב אָמַ֥ר יְהוָ֖ה וּרְפָאתִֽיו׃
(14) [The Lord] says: Build up, build up a highway! Clear a road! Remove all obstacles From the road of My people! (15) For thus said God who high aloft Forever dwells, whose name is holy: I dwell on high, in holiness; Yet with the contrite and the lowly in spirit— Reviving the spirits of the lowly, Reviving the hearts of the contrite. (16) For I will not always contend, I will not be angry forever: Nay, I who make spirits flag, Also create the breath of life. (17) For their sinful greed I was angry; I struck them and turned away in My wrath. Though stubborn, they follow the way of their hearts, (18) I note how they fare and will heal them: I will guide them and mete out solace to them, And to the mourners among them (19) heartening, comforting words: It shall be well, Well with the far and the near —said Adonai— And I will heal them.
