What is the earliest use of the term tzaddik? How far back does the concept go?

Question

According to this website, there is a claim that "It is part of our glorious tradition going back thousands of years to seek a blessing from a Tzaddik for a sick relative (see Talmud Bava Basra 116a)". However, the language they are using is as follows in the Talmud Bava Basra 116a:

The Gemara presents the third homiletic interpretation: Rabbi Pineḥas bar Ḥama interpreted a verse homiletically: Anyone who has a sick person in his home should go to a sage, and the sage will ask for mercy on the sick person’s behalf, as it is stated: “The wrath of a king is as messengers of death; but a wise man will pacify it” (Proverbs 16:14)

Essentially, they are using the word sage. However, as far as I'm aware, a sage and a tzaddik are not necessarily identical in meaning. By "tzaddik" I mean a deeply righteous and "saintly" person whose mere presence causes others to become more spiritually developed and enlightened and causes them to attach themselves to the person. Therefore, this made me wonder a) what is the earliest use of the term tzaddik, both in meaning and in literal form/word b) How long back does the concept of a tzaddik go, even if it wasn't termed a tzaddik necessarily?

Answer 1

The earliest reference is in the Torah regarding Noach (Bereishit 6:9):

אֵ֚לֶּה תּוֹלְדֹ֣ת נֹ֔חַ נֹ֗חַ אִ֥ישׁ צַדִּ֛יק תָּמִ֥ים הָיָ֖ה בְּדֹֽרֹתָ֑יו אֶת־הָֽאֱלֹהִ֖ים הִֽתְהַלֶּךְ־נֹֽחַ׃

These are the generations of Noah. Noah was in his generations a man righteous and wholehearted; Noah walked with God.

Rashi says that the main progeny of tzaddikim are in their good deeds. He also discusses what "in his generation" means, which can be understood positively or negatively. Either way, Hashem 'walked' with Noah.

The next reference to tzaddikim is regarding Avraham entreating Hashem not to destroy Sdom (Bereishit 18:23). The argument Avraham provided was that it would not be just to destroy tzaddikim and resha'im together. Whatever these 'tzaddikim' were, as defined by Avraham, he saw that in their merit no one should be destroyed in Sdom. From this we could learn that the actions of tzaddikim (even a few) outweigh the iniquity of resha'im. To this extent, the whole of Sdom could have been saved (or would have merited being saved) on account of the actions of the tzaddikim.