וַיֹּאמַ֗ר אָנָּ֤ה יְהוָה֙ זְכָר־נָ֞א אֵ֣ת אֲשֶׁ֧ר הִתְהַלַּ֣כְתִּי לְפָנֶ֗יךָ בֶּֽאֱמֶת֙ וּבְלֵ֣ב שָׁלֵ֔ם וְהַטּ֥וֹב בְּעֵינֶ֖יךָ עָשִׂ֑יתִי וַיֵּ֥בְךְּ חִזְקִיָּ֖הוּ בְּכִ֥י גָדֽוֹל׃ (ס)
и сказал: 'Помни, Господи, Я умоляю Тебя, как я ходил пред Тобою с истиной и от всего сердца и сделал то, что хорошо для Твоего взгляда.' И Езекия плакал от боли.
Tanya
Yet, all that was said above is about completing the atonement and the cleansing of the soul for G-d, as explained earlier based on the Talmud's first chapter of Zevachim, that the burnt-offering is a tribute after the intercessor's appeasement and so on. However, the beginning and foundation of the mitzvah of repentance is to return to truly G-d with a complete heart and it is necessary to explain this well and at great length, beginning with a quote from the holy Zohar in explaining the word "Teshuva-repentance" in the manner of mysticism: "Teshuv-hey. The lower hey - the lower teshuvah, the higher hey - the higher teshuvah."