Where in the Tanakh, on a peshat level, is "Yetzer HaTov" derived?

Question

Where in the Tanakh, on a peshat level, is "Yetzer HaTov" derived?

Rashi seems to derive "Yetzer HaRa" from Genesis 8:21 (because the words "yetzer" and "ra" are mentioned there):

And the Lord smelled the pleasant aroma, and the Lord said to Himself, "I will no longer curse the earth because of man, for the imagination of man's heart is evil from his youth, and I will no longer smite all living things as I have done.

https://www.chabad.org/library/bible_cdo/aid/8172/jewish/Chapter-8.htm/showrashi/true

If Rashi or the rabbis derived "Yetzer HaRa" from Genesis 8,21, because both the words "yetzer" and "ra" are mentioned there (which I accept as satisfying the peshat level); where, therefore, in the Tanakh is "Yetzer HaTov" derived?

The possible answer given by Rashi is somewhat of a stretch from a peshat level. I am therefore still looking for a Tanakh source on a peshat level.

So, for information, Rashi seems to suggest that "yetzer hatov" is derived from a poetic passage, Kohelet 4:13, where neither the words "yetzer" or "tov" exist:

"Better a poor and wise child than an old and foolish king, who no longer knows to receive admonition."

Better a poor and wise child: This is the good inclination, and why is it called a child? Because it does not enter man until thirteen years.

https://www.chabad.org/library/bible_cdo/aid/16465/showrashi/true

Again, I find this quite a stretch to relate to "Yetzer HaTov" on a peshat level; and I am therefore still looking for a Tanakh source on a peshat level. (Please note, my quesion is not whether Yetzer HaTov exists or not; but, where in the Tanakh, is it derived, on a peshat level?)

Answer 1

Here's one place...

It says in Zecharia 4:14

וַיֹּ֕אמֶר אֵ֖לֶּה שְׁנֵ֣י בְנֵֽי־הַיִּצְהָ֑ר הָעֹמְדִ֖ים עַל־אֲד֥וֹן כָּל־הָאָֽרֶץ׃

And he said, “These are the two anointed dignitaries who attend the Lord of all the earth.”

And Rashi over there writes:

שני בני היצהר. יצר טוב ויצר הרע מתהפך לטוב בזכות התורה

A good inclination, and a bad inclination can switch over to good in the merit of the Torah

Answer 2

You don't need to scan the entire Tanach. You only need to look at the language of the Torah itself.

It is first necessary to emphasize that the word Yetzer (יצר) means to form or fashion something from something else which preceded it.

Bereshit 2:9 states explicitly:

וַיַּצְמַ֞ח יְהוָ֤ה אֱלֹהִים֙ מִן־הָ֣אֲדָמָ֔ה כָּל־עֵ֛ץ נֶחְמָ֥ד לְמַרְאֶ֖ה וְט֣וֹב לְמַאֲכָ֑ל וְעֵ֤ץ הַֽחַיִּים֙ בְּת֣וֹךְ הַגָּ֔ן וְעֵ֕ץ הַדַּ֖עַת ט֥וֹב וָרָֽע׃

That there is a specific tree in the midst of G-d's garden that was comprised of a union of Tov and Rah. And it only emphasizes this about a single tree. All the other trees were desirable in appearance and comprised of good only, for use as food.

In Bereshit 3:5 it goes on to say:

כִּ֚י יֹדֵ֣עַ אֱלֹהִ֔ים כִּ֗י בְּיוֹם֙ אֲכָלְכֶ֣ם מִמֶּ֔נּוּ וְנִפְקְח֖וּ עֵֽינֵיכֶ֑ם וִהְיִיתֶם֙ כֵּֽאלֹהִ֔ים יֹדְעֵ֖י ט֥וֹב וָרָֽע׃

The Nachash reported to Chava, Adam's wife, that when they eat the fruit from this tree which is a mixture of Tov and Rah, they will acquire its quality. In other words, you are, or become, what you eat.

This too is the plain meaning of the text. If you eat healthy things, your physical body as well as your intellectual and emotional traits absorb and incorporate the healthy elements of the food. If you consume unhealthy things, the opposite happens.

This means that originally, Adam and Chava were desireable in appearance and comprised of good only. They had not eaten from the Tree of Knowledge of Tov and Rah. Only after consuming the fruit of that tree which contained a mixture of Tov and Rah, did they acquire that dual nature.

And then further in the Torah, in Devarim 20:19 which says:

כִּֽי־תָצ֣וּר אֶל־עִיר֩ יָמִ֨ים רַבִּ֜ים לְֽהִלָּחֵ֧ם עָלֶ֣יהָ לְתָפְשָׂ֗הּ לֹֽא־תַשְׁחִ֤ית אֶת־עֵצָהּ֙ לִנְדֹּ֤חַ עָלָיו֙ גַּרְזֶ֔ן כִּ֚י מִמֶּ֣נּוּ תֹאכֵ֔ל וְאֹת֖וֹ לֹ֣א תִכְרֹ֑ת כִּ֤י הָֽאָדָם֙ עֵ֣ץ הַשָּׂדֶ֔ה לָבֹ֥א מִפָּנֶ֖יךָ בַּמָּצֽוֹר׃

It emphasizes this same concept in the prohibition against cutting down the surrounding fruit trees when making war against a city because you may come to eat those fruit in the future. And it states plainly that a human being is a tree in the field. You incorporate the qualities of the fruit from those trees which you eat and become like them.

And in case this idea seems confusing, it is also emphasized in Devarim 1:39 when Moshe explains who will be permitted to enter the land of Israel, who will not enter and why.

וְטַפְּכֶם֩ אֲשֶׁ֨ר אֲמַרְתֶּ֜ם לָבַ֣ז יִהְיֶ֗ה וּ֠בְנֵיכֶם אֲשֶׁ֨ר לֹא־יָדְע֤וּ הַיּוֹם֙ ט֣וֹב וָרָ֔ע הֵ֖מָּה יָבֹ֣אוּ שָׁ֑מָּה וְלָהֶ֣ם אֶתְּנֶ֔נָּה וְהֵ֖ם יִירָשֽׁוּהָּ׃

That at the Giving of the Torah, the effect from the Tree of Knowledge of Tov and Rah which had been acquired by Adam and Chava was removed from the nation of Israel. And in that 40 day time period while Moshe was on Mount Sinai, one of the four time categories for length of pregnancy mentioned in the Oral Torah, children were conceived who did not have the quality of that mixture of Tov and Rah. And ultimately, those children were among the ones permitted to enter the Land of Life, the Land of Israel.