אָמַר רַבִּי יִצְחָק מִפְּנֵי מָה הָיוּ אֲבוֹתֵינוּ עֲקוּרִים מִפְּנֵי הַקָּדוֹשׁ בָּרוּךְ הוּא מִתְאַוֶּה לִתְפִלָּתָן שֶׁל צַדִּיקִים אָמַר רַבִּי יִצְחָק לָמָּה נִמְשְׁלָה תְּפִלָּתָן שֶׁל צַדִּיקִים כְּעֶתֶר מָה עֶתֶר זֶה מְהַפֵּךְ הַתְּבוּאָה מִמָּקוֹם לְמָקוֹם כָּךְ תְּפִלָּתָן שֶׁל צַדִּיקִים מְהַפֶּכֶת מִדּוֹתָיו שֶׁל הַקָּדוֹשׁ בָּרוּךְ הוּא מִמִּדַּת רַגְזָנוּת לְמִדַּת רַחֲמָנוּת אָמַר רַבִּי אַמֵּי אַבְרָהָם וְשָׂרָה טוּמְטְמִין הָיוּ שֶׁנֶּאֱמַר הַבִּיטוּ אֶל צוּר
Rabbi Yitzḥak said: For what reason were our forefathers initially infertile? Because the Holy One, Blessed be He, desires the prayers of the righteous, and He therefore wanted them to pray for children. Similarly, Rabbi Yitzḥak said: Why are the prayers of the righteous compared to a pitchfork [eter], as in the verse: “And He let Himself be entreated [vaye’ater]”? This indicates that just as this pitchfork turns over produce from one place to another, so the prayer of the righteous turns over the attributes of the Holy One, Blessed be He, from the attribute of rage to the attribute of mercy. Rabbi Ami said: Abraham and Sarah were originally tumtumin, people whose sexual organs are concealed and not functional, as it is stated: “Look to the rock