The Torah is the words of the covenant
“אֵלֶּה דִבְרֵי הַבְּרִית אֲשֶׁר-צִוָּה יְהוָה אֶת-מֹשֶׁה, לִכְרֹת אֶת-בְּנֵי יִשְׂרָאֵל–בְּאֶרֶץ מוֹאָב: מִלְּבַד הַבְּרִית, אֲשֶׁר-כָּרַת אִתָּם בְּחֹרֵב”
“These are the words of the covenant which the LORD commanded Moses to make with the sons of Israel in the land of Moab, besides the covenant which He had made with them at Horeb.”
Rabbi Chiya discusses the curses mentioned in the portion of Bechukotai in relation to the covenant.
“וְזָכַרְתִּי, אֶת-בְּרִיתִי יַעֲקוֹב; וְאַף אֶת-בְּרִיתִי יִצְחָק וְאַף אֶת-בְּרִיתִי אַבְרָהָם, אֶזְכֹּר–וְהָאָרֶץ אֶזְכֹּר”
“then I will remember My covenant with Jacob, and I will remember also My covenant with Isaac, and My covenant with Abraham as well, and I will remember the land.”
He said that it should say ‘the words of the Gevurah’ that is the Left and aspect of judgments. The curses in Leviticus were said from the aspect of Judgment and the curses in Deuteronomy were said by Moses.
They continue to say that both sets of curses are the words of the covenant. Even though they express judgments, they include from good and bad. The good comes from Yessod that is the aspect of Tzadik, righteous. The bad comes from the place of judgment, which is Malchut. The connection of Yessod and Malchut is called ‘covenant’. Yessod is Light and the aspect of day. Malchut doesn’t have light of its own and is the aspect of night. The connection between them described in Genesis 1:5
“וַיִּקְרָא אֱלֹהִים לָאוֹר יוֹם וְלַחֹשֶׁךְ קָרָא לָיְלָה וַיְהִי עֶרֶב וַיְהִי בֹקֶר יוֹם אֶחָד”
“God called the light day, and the darkness He called night. And there was evening and there was morning, one day.”
For the reason that the connection between Zeir Anpin and Malchut is always through Yessod, the Torah mentions the covenant.